Wednesday 30 September 2020

Chess Evolution: The French Defence (conclusion)

THE French Defence will doubtless continue evolving and, I suspect, remain particularly popular at club level because there is a perception - probably a correct one - that there is less crucial theory after 1.e4 e6 than after the more-popular continuations 1...c5 and 1...e5.
Here I want to go through a 'game' that consists of both sides playing the most-popular continuation in ChessBase's 2020 Mega database, starting with the position after 1...e6.
White - Black
French Winawer
1.e4 e6 2.d4 d5 3.Nc3 Bb4!?
I am slightly surprised this is more common, at least in Mega20, than the Classical 3...Nf6.
4.e5 c5 5.a3 Bxc3+ 6.bxc3 Ne7
This is massively more popular than second-choice 6...Qc7.
7.Qg4 Qc7
This beats 7...0-0 by 4,677 appearances to 4,008.
8.Qxg7 Rg8 9.Qxh7 cxd4 10.Ne2 Nbc6 11.f4 Bd7 12.Qd3 dxc3 13.Nxc3 a6 14.Rb1 Na5 15.h4 Nf5 16.Rh3 0-0-0 17.h5 Nc4 18.h6 Rg6 19.h7 Rh8 20.Rb4 Bc6
Position after 20.Bc6
This position occurs 12 times in Mega20, with two moves being equally popular, having been played four times each: 21.Qd1 and 21.Ne2. The position first occurred in 1992 and last appeared in 2016. White is a pawn up and has the bishop-pair, but Black has two great knights and - probably - the safer king. The analysis engines Stockfish11 and Komodo11.01 reckon the position is dead-equal.

Tuesday 29 September 2020

New Hastings Update

THIS has just appeared at the Hastings congress site:

After due deliberation by the Chairman, organisers and sponsors, it is with great regret that we confirm the Caplin Hastings International Chess Congress 2020-2021 will not take place. In view of the increase in the spread of Covid-19, it has been decided that the risk involved in holding the event would be high, and the risk of last-minute cancellation equally high. Although several alternative formats were considered, to comply with social distancing, it was agreed that neither sponsors nor organisers would wish to risk the chance of any player contracting the virus.
It was with great reluctance that the decision was taken, as this would have been the centenary of the event in its present form. However, we shall postpone and not cancel the centenary celebrations, which we intend will take place next year.

Chess Evolution: The French Defence (part 13)

WORLD champions set trends in openings, which is why the French Tarrasch: 1.e4 e6 2.d4 d5 3.Nd2 experienced a major revival when Karpov used it to grind down opponents, apart from Korchnoi, in the 1970s.
Even Kasparov played the Tarrasch, as well as 3.Nc3, and he also revived the Exchange Variation: 3.exd5.
In more recent times there has been a trend for Black to try moves that would have been regarded as bordering on heresy a generation earlier.
After 1.e4 e6 2.d4 d5 3.Nd2, some strong players started playing the wait-and-see 3...a6!?
This first appears in ChessBase's 2020 Mega database in 1948, with Botvinnik among its early experimenters.
One of the ideas is that after White's most-popular reply, 4.Ngf3, play can continue 4...c5 5.exd5 exd5 without White having the potentially simplifying Bb5+.
Even more outrageous to classical eyes is 1.e4 e6 2.d4 d5 3.Nc3 h6!?, when Black does not have the excuse that White has played slowly with Nd2, blocking the white dark-squared bishop.
This first appears in Mega20 in 1965. By early 1998 it had been played six times, resulting in six black wins.
Farrukh Amanotov (2632) - Vadim Malakhatko (2462)
Astana (Kazakhstan) 2019
French 3.Nc3 h6
1.e4 e6 2.d4 d5 3.Nc3 h6!? 4.Nge2!?
An unusual positional approach that Amanotov presumably prepared beforehand as Malakhatko is well-known for playing 3...h6!? Most popular are 4.Nf3 and 4.Bd3. For what it is worth, the analysis engines Stockfish11 and Komodo11.01 also like 4.Be3!?
4...dxe4 5.Nxe4 Nd7 6.g3 Ngf6 7.Nxf6+ Nxf6 8.Bg2 Bd6!?
Instead of playing the pawn-break ...c5, Malakhatko has in mind ...e5.
9.0-0 0-0 10.c4 c6
Blunting the g2 bishop, but also giving the d6 bishop a retreat that keeps it on the b8-h2 diagonal.
11.Nc3 e5 12.c5 Bc7 13.c5
White ensures there will be an unbalanced pawn-structure.
13...cxd5 14.Nxd5 Nxd5 15.Bxd5 Qe7 16.Qc2 Rd8 17.Bg2 f5
White's queenside pawn-majority could be a trump in an endgame, but for now Black's kingside/central pawn-majority is at least as important.
18.b4 e4 19.Bb2 Be6 20.Rfd1 Qf7 21.Bf1!? Rxd1 22.Rxd1 Bxa2 23.b5?!
White has good compensation for the pawn after 23.c6 bxc6 24.Qxc6, according to the engines.
23...Bb3
This is the best move, according to the engines, although, contrary to first impressions, it does not win the exchange.
24.Qc3 Re8
Not 24...Bxd1?? 25.Bc4.
25.Rd2 f4 26.Qxg7+ Qxg7 27.Bxg7 e3!?
Also roughly level is 27...Kxg7 28.Rd7+ Kf6 29.Rxc7.
28.Rd7 e2 29.Bxe2 Rxe2 30.Rxc7 Bd5 31.Kf1 f3 32.h4

Black to play and draw

32...h5?
Black has a draw after 32...Rd2 33.Kg1 Rd1+ 34.Kh2 Rd2 etc.
33.Kg1 Re1+ 34.Kh2 Rb1
The problem for Black is that 34...Re2 is simply met by 35.Bd4, eg 35...Re4 36.Bc3 (not 36.Be3? Rxe3!) Rc4 37.Bd2 Rd4 38.Be3 Rb4 39.Rd7 Be4 40.g4! hxg4 41.h5 with winning play on the kingside, according to the engines.
35.Bf6 Rb5 36.g4! Rb4
Very good for White is 36...hxg4 37.h5.
37.gxh5 Rf4 38.Bg5?
Better is 38.Rc8+, forcing Black to play 38...Kf7, after which 39.Bg5 is very strong for White as Black cannot force rooks off.
38...Rf7 39.Rc8+ Rf8 40.Rc7 Rf7 41.Be7
White keeps rooks on, but his winning chances have gone.
41...Kh7 42.Kg3 a5 43.Bd6 ½–½

Monday 28 September 2020

Chess Evolution: The French Defence (part 12)

BOTVINNIK'S successes with the Winawer led to a surge of interest in the French Defence.
It was not long before some people started questioning whether 2.d4 was, after all, the best response.
How about playing some other move that did not provide a target for Black's ...c5, and at the same time supported the undefended e4 pawn?
Bobby Fischer - Uzi Geller
Netanya (Israel) 1968
King's Indian Attack
1.e4 e6 2.d3
Despite Fischer's reputation for having played the King's Indian Attack against the French, he actually played it much more often after the Sicilian, ie 1.e4 c5 2.Nf3 e6 3.d3.
2...d5 3.Nd2 c5 4.g3
More common is 4.Nf3, although the two moves often transpose.
4...Nf6 5.Bg2 Be7 6.Ngf3 0-0 7.0-0 Nc6 8.Re1 Qc7!?
The move ...Qc7 often has a dubious reputation in the KIA as White can get to play a breakthrough sac, as happens in this game. However in this line 8...Qc7!? has been played by such divergent talents as Larsen, Kramnik and Nakamura, so I guess it must be fine.
9.e5 Nd7 10.Qe2 b5 11.h4 a5 12.Nf1 Nd4!?
Larsen played 12...Ba6; French expert Uhlmann once played 12...a4 but later switched to 12...b4.
13.Nxd4 cxd4 14.Bf4 Ra6!?
It is easy to suspect this is a misprint for 14...Ba6, but the two moves are equally popular in ChessBase's 2020 Mega database.
15.Nh2 Rc6
This is the point of 14...Ra6!? Black puts pressure on c2, but after ...
16.Rac1
...it is not obvious how Black can increase the pressure.
16...Ba6?!
The position after 16.Rac1 has been reached seven times in Mega20, with the text being chosen on three occasions. The analysis engines Stockfish11 and Komodo11.01 give 16...Bb4 with equal chances.
17.Bxd5!
This is the breakthrough sac that is common in the KIA when Black plays ...Qc7.
17...exd5 18.e6 Qd8 19.exd7 Re6 20.Qg4 f5
Or 20...Qxd7 21.Rxe6 Qxe6 22.Qxe6 fxe6 23.Re1, when the engines reckon Black's pawn weaknesses give White a large advantage.
21.Qh5 Qxd7 22.Nf3 g6
Better, according to the engines, is 22...Rb6!?, but is hard to believe it saves Black.
23.Qh6 Bf6 24.Rxe6 Qxe6

How should White proceed?
25.Be5!?
White has many good moves, but the key is to avoid 25.Re1? Qxe1+! 26.Nxe1 Bg7 27.Qg5 Bf6 etc.
25...Bxe5 26.Re1 f4 27.Rxe5 Qd7 28.h5 fxg3 29.hxg6 gxf2+ 30.Kxf2 hxg6 31.Qxg6 Qg7 32.Rg5 1-0

Sunday 27 September 2020

Chess Evolution: The French Defence (part 11)

AS international chess returned to normal, and indeed increased, after World War One, there was a big question mark over the Winawer: 1.e4 e6 2.d4 d5 3.Nc3 Bb4.
The statistics bear this out. Of the games with 1.e4 e6 2.d4 d5 3.Nc3 from 1919-27 in ChessBase's 2020 Mega database, 358 continued with the Classical: 3...Nf6 compared with just 105 for 3...Bb4.
The main reason for the relative unpopularity of 3...Bb4 was 4.exd5, which was played in 67 of the 105 games.
It was thought that switching into a line of the Exchange Variation: 1.e4 e6 2.d4 d5 3.exd5 was detrimental to Black because in that variation the black dark-square bishop was believed to be best-placed on d6.
Then came game one of the Capablanca - Alekhine world championship, in which Capablanca played 4.exd5 against Alekhine's Winawer and lost.
From 1928-39, when World War Two brought another cessation to most international chess, 3...Nf6 featured in 631 Mega20 games compared with 262 for 3...Bb4.
In other words the percentage of Winawer games, compared with Classical, rose from 22.7% to 29.3%.
That was significant, but even more dramatic was the eclipse of 4.exd5 as the preferred answer to the Winawer.
It was played 63.8% of the time from 1919-27 but just 16.8% from 1928-39.
The new kid on the block - actually, not so new but suddenly much more popular - was 4.e5, which accounted for 55% of the games from 1928-39.
The main champion of the Winawer became Mikhail Botvinnik. He played it throughout the 1930s, continued (when he could) during World War Two and kept faith with it in the 1948 tournament to decide who should replace the deceased Alekhine as world champion.
Samuel Reshevsky - Mikhail Botvinnik
1948 World Championship Round 19
French Winawer
1.d4 e6 2.e4 d5 3.Nc3 Bb4 4.e5 c5 5.a3
This is now firmly established as the main move but for a long time it played second fiddle to 5.Bd2.
5...Bxc3+!?
Botvinnik won with 5...Ba5 against the same opponent two years earlier at Moscow in a match between the Soviet Union and the US.
6.bxc3 Qc7 7.Qg4!?
Reshevsky was noted for his positional play, while also excelling at tactics. At the time this game was played, the main move was the non-forcing 7.Nf3, but here Reshevsky aims to take advantage of Black's vulnerability on the kingside dark squares.
7...f5!?
A major alternative is 7...Ne7, transposing to a position normally reached via the move-order 6...Ne7 7.Qg4 Qc7.
8.Qg3!?
The first game in Mega20 to feature this move, which is now standard.
8...cxd4 9.cxd4 Ne7 10.Bd2
Not 10.Qxg7?? Rg8 and 11...Qc3+ etc.
10...0-0 11.Bd3
Defending c2 and hoping to later lever open the b1-h7 diagonal.
In many lines of the Winawer with Qg4, Black sacrifices one or two kingside pawns in return for dynamic piece-play on the queenside and in the centre. Here material is level but positionally unbalanced - White has more space and kingside attacking chances, while Black has pressure down the half-open c file and generally the better of it on the queenside.
White also has the bishop-pair, although the blocked centre means that is not an advantage at present. Nevertheless Black has a bad bishop, so Botvinnik sets about exchanging it.
11...b6 12.Ne2 Ba6 13.Nf4 Qd7 14.Bxa6!?
The point of voluntarily exchanging is that the black queen's knight has few immediate prospects on a6.
14...Nxa6 15.Qd3 Nb8 16.h4 Nbc6 17.Rh3 Rac8 18.Rg3 Kh8
Kasparov (2795) - Short (2690), Novgorod (USSR) 1997, saw 18...Rf7 19.h5 Nd8 20.c3* with an edge for White, according to the analysis engines Stockfish11 and Komodo11.01 (1-0, 31 moves).
19.h5 Rf7 20.h6 g6 21.Rc1!?
A rule-of-thumb from Cecil Purdy, the first world correspondence champion, was to never put a rook behind an unmoved pawn, even if you intend to move the pawn fairly quickly. Such rules are often broken, correctly, but here the engines much prefer 21.a4 or 21.Kf1!?
21...Rff8!? 22.Nd2
White's kingside pressure has not resulted in a breakthrough, but he still has an edge, according to the engines. However, Black now has time to try to work up an initiative on the queenside.
22...Nb8!?
Opening a line for the queen's rook, but the engines are unimpressed, preferring 22...Nd8 with the idea of proceeding with ...Nf7!?
23.Kf1 Rc4
A rook in the middle of the board in a crowded middlegame can easily get into trouble, but it will be hard for the white knight to harass it.
24.Kg1 Nbc6!? 25.Bg5 Ng8 26.Re1 Qf7 27.c3 Na5
Botvinnik decides the knight is a better occupant of the c4 outpost.
28.Nf4 Rc6
Defending e6 as well as clearing the c4 square and possibly preparing to add pressure down the c file with ...Rfc8.
29.Bf6+?
A serious misjudgment. The engines reckon White keeps an edge - "winning," according to Stockfish11, "slight," according to Komodo11 - with a move such as 29.a4.
29...Nxf6 30.exf6
How should Black proceed?
30...Nc4
Did Reshevsky miss this simple zwischenzug? White is massively better after 30...Qxf6? 31.Rge3, but 30...Nc4 scuppers Reshevsky's plans.
31.Qb1 Qxf6
The net result of 29.Bf6+? is that White has lost a pawn and exchanged an active bishop for an inactive knight.
32.a4 g5
Botvinnik seizes the initiative on the kingside while the white pieces are uncoordinated.
33.Nd3 f4 34.Rh3 g4 35.Rh1 Rc7 36.Qd1 Qg6 37.Rh4 f3 38.g3
Reshevsky has been able to close lines on the kingside, but his forces remain uncoordinated. His one plus is pressure against the weak e pawn.
38...Rcf7?
Abandoning the c file lets White off the hook. The engines reckon Black keeps an edge with 38...Rfc8 or 38...Rf6.
39.Nf4?
Walking into a simple and very strong exchange sac. The position seems equal after 39.Ne5 Nxe5 40.Rxe5, White's giving up the c file meaning he cannot reply 40...Rxc3.
39...Rxf4! 40.gxf4 Rxf4
Black has two pawns and a powerful attack for the exchange.
41.Qb1
This is best, according to the engines, but White is already busted.
41...Rf5 42.Qd3
The engines give 42.Re4 or 42.Kh2 as best but in each case a simple answer is 42...Nd2.
42...g3 43.Qf1 gxf2+ 44.Kxf2 Rg5 45.Qh3 Rg2+ 46.Kf3 Nd2+ 47.Ke3 Rg3+ 0-1
*The move-count was one less in Kasparov-Short, but the game reached the same position as in Reshevsky-Botvinnik.

Saturday 26 September 2020

Chess Evolution: The French Defence (part 10)

TARRASCH'S 3.Nd2 quickly became a popular weapon against the French, but another move, 3.e5, first mentioned by Greco in 1620 (see part one of this series) was revived by Nimzowitsch in the run-up to World War One.
The move 3.e5 had never fallen completely from favour, being extensively used by the Paulsen brothers, Wilfried and Louis, in the 1870s and 1880s, and by Steinitz in the 1890s.
Nimzowitsch played 3.e5 three times at Karlsbad 1911, drawing with Rubinstein but beating Salwe and Levenfish.
The move really took off the following year when at San Sebastian he used it to beat Tarrasch, Speilmann, Duras and Leonhardt.
Aron Nimzowitsch - Siegbert Tarrasch
San Sebastian 1912
French Advance
1.e4 e6 2.d4 d5 3.e5
This move divided opinion in the early 1900s and still does today. Is White punishing Black for failing to take his full share of the centre, or is White spending time on over-extending?
3...c5 4.c3 Nc6 5.Nf3 Qb6 6.Bd3!?
More common today are 6.Be2 and especially 6.a3.
6...cxd4 7.cxd4 Bd7
There are 71 examples in ChessBase's 2020 Mega database of Black falling for the well-known trap 7...Nxd4??, which loses because of 8.Nxd4 Qxd4?? 9.Bb5+ etc.
8.Be2!?
More popular today, but not necessarily better, is the Milner-Barry Gambit, starting with 8.0-0!?
The position after 8.Be2!? can also be reached if White plays 6.Be2 instead of 6.Bd3, in which case White gains a tempo as it would be his turn to move. But after 6.Be2 Black is not obliged to play an early ...Bd7, so 6.Bd3 followed by 8.Be2!? only loses a tempo if Black plays inaccurately.
8...Nge7 9.b3?!
This is probably too slow - 12 rounds later, against Duras, Nimzowitsch switched to 9.Na3.
9...Nf5 10.Bb2 Bb4+ 11.Kf1
The only way to save the d4 pawn.
11...Be7!?
The point of this move, which Tarrasch had played against Louis Paulsen 24 years earlier, is so 12.g4?! can be met by 12...Nh4. Rubinstein at Karlsbad prevented g4 by playing 11...h5. But according to Nimzowitsch, Black can play 11...0-0! (Nimzowitsch's punctuation) as 12.g4 Nh6 (12...Nfe7? 13.a3) is nothing to be feared.
12.g3 a5 13.a4
The text was also played against Tarrasch by Louis Paulsen at the Bavarian Congress (Nürnberg) 1888. Note that trying to stop ...a4 with 13.Nc3 does not work as 13...a4 14.Nxa4?! runs into 14...Rxa4 15.bxa4 Qxb2.
13...Rc8 14.Bb5 Nb4?!
Connecting rooks by 14...0-0, as suggested by the analysis engines Stockfish11 and Komodo11.01, seems better.
15.Nc3!?
Paulsen played 15.Bxd7+ against Tarrasch. After 15...Kxd7 16.Nc3 Black could have kept an edge, according to the engines, with 16...h5, when White's king seems the more vulnerable. The game saw 16...Nc6 17.Nb5 Na7 18.Nxa7 Qxa7 with a roughly level game (but 0-1, 62 moves).
15...Na6 16.Kg2 Nc7 17.Be2 Bb4
Tarrasch presumably had in mind keeping his king in the centre, as he did against Paulsen.
18.Na2 Na6 19.Bd3 Ne7 20.Rc1 Nc6 21.Nxb4 Naxb4
White has the bishop-pair, but the position remains fairly closed. The one major warning sign for Black, perhaps, is that his kingside is somewhat denuded of pieces.
22.Bb1 h6 23.Bb1 Ne7 24.Rxc8+ Bxc8 25.Ne1 Rf8 26.Nd3 f6 27.Nxb4 Qxb4 28.exf6 Rxf6 29.Bc1?
Nimzowitsch gave this an exclamation mark, but missed a tactical point of the position. Better is 29.Re1.
How can Black take advantage of White's last move?
*****
*****
*****
*****
*****
29...Nc6?
Black has a very good game after 29...e5 as 30.dxe5? runs into 30...Bxg4.
30.g5 hxg5 31.Bxg5 Rf8 32.Be3 Qe7?!
The engines reckon ...e5 is still Black's best shot, although the position is no longer favourable to him.
33.Qg4
Preventing 33...e5 by pinning the e pawn.
33...Qf6 34.Rg1 Rh8 35.Rh1 Rh4?
The engines reckon 35...Bd7 is decidedly better.
36.Qg3
There is no good answer to this, which leaves White threatening Bg5 and Qxg7.
36...Rxd4
Tarrasch hopes his central pawn-duo, along with depriving White of the bishop-pair, will compensate for the exchange.
37.Bxd4 Nxd4 38.Qxg7 Qf3+
Or 38...Qxg7 39.Rxg7 Nxb3 40.Rg8+ Kd7 41.h4 etc.
39.Qg2 Qxg2+ 40.Rxg2 Nxb3 41.h4 1-0

Friday 25 September 2020

Chess Evolution: The French Defence (part nine)

AFTER 1.e4 e6 2.d4 d5, the moves 3.exd5, 3.e5 and the relatively new-fangled 3.Nc3 all had their plus and minus points.
From a historical basis, using ChessBase's 2020 Mega database as the source, the next move to be tried, in 1859, was 3.Bd3.
It never really caught on, not least because after 3...dxe4 4.Bxe4 Nf6, White had to either cede the bishop-pair or spend a tempo moving the light-square bishop for a third time.
The move 3.Nc3 continued to grow in importance, even though it blocks the white c pawn from supporting d4 and allows Black to increase pressure on e4 by playing the Winawer: 3...Bb4 or the McCutcheon: 3...Nf6 4.Bg5 Bb4.
Then in 1890, at the British Chess Association Congress in Manchester, Tarrasch unveiled a way of side-stepping both those variations without committing to moving the e pawn, namely 3.Nd2 (he had played the move previously in casual games, but Manchester seems to have been its competitive debut).
Steinitz was an early convert, and soon the Tarrasch Variation appeared in the repertoires of many of the leading masters of the late-19th century including Pillsbury, Schlechter and Albin.
Ironically Tarrasch gave up his variation in 1894, largely due to games like the following.
Siegbert Tarrasch - Karl Eckart
Nürnberg (Friendly) 1891
French Defence
1.e4 e6 2.d4 d5 3.Nd2 c5
The most-popular move in Mega20 is 3...Nf6, but the text is a logical way of taking advantage of the fact that a knight on d2 does not pressurise Black's centre in the way a knight on c3 does. For Tarrasch, 3...c5 was a virtual refutation of his system as Black is almost assured of obtaining an isolated queen's pawn - something Tarrasch believed greatly benefits Black.
4.exd5 exd5 5.dxc5!?
This move is still occasionally played by grandmasters, although it has been overtaken in popularity by 5.Ngf3 and 5.Bb5+.
5...Bxc5 6.Nb3
White regains the tempo that was arguably lost in capturing on c5 before Black had moved his dark-square bishop.
6...Bb6 7.Nf3 Nf6 8.Be2 Nc6 9.c3 0-0 10.0-0 Ne4!?
An interesting and aggressive choice. Instead of developing another piece (for example ...Bf5, ...Bg4 or ...Re8), Eckart occupies a central outpost in his opponent's half of the board, probably hoping for a kingside attack.
11.Bf4 Re8 12.Nfd4!?
Wrong knight?
12...Qf6 13.Be3 Qg6 14.Re1 Bh3 15.Bf1 Ne5
Black's pieces are gathering ominously in the region of White's king. The position is roughly equal, according to the analysis engines Stockfish11 and Komodo11.01, but such positions are usually easier for the attacker to play.
16.f3 Nd6 17.Kh1?!
Seeking to drive away the Black light-square bishop, but White's position turns out to be looser than it may seem. White needs to play a consolidating move such as 17.Bf2.
17...Nec4
Even stronger is the engines' 17...Bxg2+! 18.Bxg2 Nd3, the point being that 19.Re2? loses to 19...Rxe3! since 20.Rxe3? runs into 20...Nf2+.
18.Bf2 Rxe1 19.Qxe1 Re8 20.Qc1 Bd7 21.Nd2 Bc7?!
Black keeps a pleasant edge with 21...Ne3, according to the engines.
22.b3?
More-or-less forcing Black to make the knight entry he missed last time. The engines reckon White equalises with 22.Nxc4.
22...Ne3 23.Bxe3 Rxe3 24.Be2 Nf5 25.Nf1 bf4 26.Nxf5?!
White is holding on after 26.Qb2.
How should Black proceed?
*****
*****
*****
*****
*****
26...Qxg2+! 27.Kxg2 Rxe2+ 28.Kg1 Bxc1 29.Rxc1 Bxf5
Black has won a pawn, got his rook to the seventh rank and has the more-active minor piece.
30.Ng3 Rc2 31.Rd1!?
Objectively better may be 31.Rxc2, but White should eventually be ground down.
The game finished:
31...Be6 32.c4 Rxa2 33.cxd5 Bd7 34.Ne4 Rc2 35.b4 b6 36.Ra1 Rc7 37.Kf2 f5 38.Ng5 h6 39.Nh3 g5 40.f4 g4 41.Ng1 Bb5 0-1
The knight cannot move (42.Ne2? Rc2 43.Re1 Rxe2+ 44.Rxe2 Bxe2 45.Kxe2 Kf7) and meanwhile White has too many weak pawns.

Thursday 24 September 2020

Chess Evolution: The French Defence (part eight)

BLACK had one other major choice in the French Classical: 1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.Bg5, instead of 4...Bb4 and 4...Be7, and that is 4...dxe4.
The move goes back to at least 1878, but it was English master Amos Burn who popularised it in the late 1880s and the 1890s.
Carl Schlechter - Amos Burn
Berliner SG 70th Anniversary (Berlin) 1897
French Burn
1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.Bg5 dxe4 5.Nxe4 Nbd7
Today 5...Be7 is considered the main move, but Burn scored much better with the text.
6.Nf3 Be7 7.Nxf6+ Nxf6 8.Bd3 c5!?
Burn castled in a round-four win over Rudolf Charousek, as indeed he had done nine years earlier in a win over Charles Locock. But in round five of this tournament, against Richard Teichmann, he switched to the text and lost. This game against Schlecter was in round eight.
9.dxc5!?
Tecihmann preferred 9.c3.
9...Qa5+ 10.c3 Qxc5 11.Qe2
Magnus Carlsen played 11.0-0 in a 2006 win over Ulf Andersson, but the text scores very well in ChessBase's 2020 Mega database.
11...Bd7
Both players are being cagey about their castling intentions, reminding me of the dictum attributed to Pillsbury: "Castle because you will or because you must, but not because you can."
12.Ne5 Rd8
Petrosian played 12...Bc6 in a draw with Spassky in their 1966 world championship match.
13.0-0
Somewhat speculative-looking is 13.0-0-0!? but it seems playable.
13...0-0?
The analysis engines Stockfish11 and Komodo11.01 suggest 13...h6 or 13...Bd6!? The text loses material, but can you see how?
Position after 13...0-0?
*****
*****
*****
*****
*****
14.Rad1?
The position after 13...0-0? appears 12 times in Mega20 but only Ludwig Rellstab - Kurt Richter, Berlin Championship 1932, saw 14.Bxf6 Bxf6 15.Bxh7+ Kxh7 16.Qd3+ Kg8 17.Nxd7 and 18.Nxf6+. If 16...Kh8, White still emerges a pawn up after 17.Nxd7 thanks to having a queen check at h3.
14...Bc6 15.c4 Qb6 16.Qc2 h6 17.Bh4 Rd4 18.Bg3 Rfd8 19.Qe2?!
Black gets something of an initiative after this. Safer was 19.Nxc6.
19...Be4 20.Bxe4 Nxe4 21.Rxd4 Qxd4 22.Qh5 Rf8
Black has been obliged to go passive with his rook, but he commands the centre of the board.
23.b3 Bc5 24.Qe2
The engines suggest 24.Ng4 Nxg3 25.hxg3, but prefer Black after 25...f5 or 25...g6!?
24...Rd8 25.Qh5
Schlechter makes a tacit draw offer, but Burn wants more.
25...f6?
Better is 25...g6, one point being that 26.Qxh6?? loses to 26...Nxg3 and 27...Qxe5.
26.Ng4?!
Schlechter presumably saw he had a draw with 26.Qf7+ Kh7 27.Qg6+, but must have thought Burn's last move left him with winning chances.
26...e5?!
It is hard to know what both players missed as Black seems comfortably better after the simple 26..Nxg3.
27.Qg6?!
Here the engines give 27.Bh4 Ng5 25.Bxg5 hxg5 26.Ne3 with what they reckon is just a small edge for Black.
27...Kf8 28.Ne3 Nc3
Very good for Black, according to the engines, is 28...Qd3, eg 29.Nf5 Rd7 30.Qg4 Nc3, when White can hardly defend his queenside.
29.Qh7?
Correct is 29.Nf5, threatening mate and attacking the black queen at the same time. After 29...Qd7 30.Qh7 Black has no time to go after the white queenside pawns with 30...Nxa2?? as 31.Qh8+ Kf7 32.Qxg7+ Ke6 33.Qg4 leaves him busted.  Best, according to the engines, is 30...Ne2+ 31.Kh1 Qf7 with what they reckon is dead-equality.
29...Ne2+ 30.Kh1 Qd3! 31.Qxd3 Rxd3
With queens off the board, there is no longer any danger to the black king, and Black's pieces are much better coordinated than White's.
32.Rd1 Rxd1+ 33.Nxd1 Bd4 34.f3
Or 34.Ne3 Nc1 etc.
34...Nxg3+ 35.hxg3 f5 36.g4 e4 0-1
Schlechter resigned as the black e pawn will cost White his knight.

Wednesday 23 September 2020

Chess Evolution: The French Defence (part seven)

THE McCutcheon fell under a cloud after its rough treatment from Lasker in his 1908 world championship match against Tarrasch.
It was still played, especially at club level, but attention focused on what was already the main line of the French Classical: 1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.Bg5 Be7.
Lasker helped in this process by turning up on the black side of the line, continuing to play it well into the later stages of his career.
Ossip Bernstein - Emanuel Lasker
Zürich 1934
1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.Bg5 Be7 5.e5 Nfd7 6.Bxe7 Qxe7 7.Qg4!?
The move 7.Qd2 was popular in the early days of this line but today 7.f4 is established as the main try.
7...0-0 8.Nf3 c5 9.Bd3 f5!?
The most-popular move in ChessBase's 2020 Mega database, but strong players in modern times have been more likely to play 9..h6 or 9...cxd4, moves preferred by the analysis engines Stockfish11 and Komodo11.01.
10.exf6
The engines like 10.Qg5!?
10...Rxf6!?
Hans Johner had played 10...Nxf6 two rounds earlier, losing to Walter Henneberger.
11.Qh4 Nf8 12.dxc5 Qxc5 13.0-0 Nc6 14.Rae1 Bd7 15.Ne5!?
Bernstein seeks to blockade the black central pawn-duo, as taught by Nimzowitsch, but the blockade cannot be maintained. The engines suggest White should be content for now to keep the pawns under restraint, for example with 15.Qg5.
15...Nxe5 16.Rxe5 Qb6
16...Ng6 17.Bxg6 Rxg6 also looks reasonable for Black.
17.Re3 Be8!?
A well-known manoeuvre in the French - the light-square bishop seeks activity from h5 or, in this case, g6.
Bad is 17...Qxb2? 18.Rb1 Qa3 19.Nxd5!
18.Rg3 Bg6 19.Qg4 Rd8
Could Lasker here have grabbed the b2 pawn?
Position after 19.Qg4

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Yes, according to the engines, who give 19...Qxb2!? 20.Rb1 Qxc3 21.Bxg6 Qc7, reckoning White does not have sufficient compensation for the pawn.
20.b3 Rd7 21.Na4!?
Hitting the black queen, but driving it to a better square.
21...Qd6 22.Rf3 Bxd3
Starting the central pawns rolling with 22...e5!? looks promising.
23.cxd3!?
This creates a weakness, but seeks to hold up the black central pawns.
23...Rh6 24.Qg3 e5 25.Re3 b5 26.Nc3 Ng6?
If 26...d4, White replies 27.Ne4. However that is better than the text, which lets White seize the initiative.
27.d4 exd4?
The engines give 27...Qe7, but much prefer White.
28.Nxb5 Qc5 29.Qb8+?
The wrong check. After 29.Re8+ Kf7 29.Rfe1!, grabbing the knight with 29...Qxb5? loses to 30.Qf3+. The engines reckon Black's best is 29...Nf8, but then White can play 30.Nxd4 as 30...Qxd4 loses to 31.Rxf8+ Kxf8 32.Qb8+ Kf7 33.Qe8+ Kf6 34.Qe6+ Kg5 35.Re5+ etc.
29...Nf8 30.Rf3?
Bernstein had to find 30.b4! Qxb4 31.Rb3 with roughly equal chances.
30...Rb6 31.Qe8 Rf6 32.Rxf6 gxf6 33.Qe2 a6
The white knight is trapped.
34.Nxd4 Qxd4 35.Qxa6
White has two connected passed pawns for the knight, but they are a long way from queening. It is not simple for Black, however, as his king is exposed.
35...Qe5 36.Qd3 Ne6 37.g3
Objectively best, according to the engines, is 37.Qg3?!, but exchanging queens in a position such as this is tantamount to giving up.
37...d4 38.Rc1 Qd5 39.h4 Kg7 40.Re1 Nc5 41.Qd1 d3 42.b4 Ne4 43.Qf3 Nc3 44.Qg4+ Kf7 0-1
Lasker's technique in keeping his pieces (apart from the king) centralised while gradually advancing the d pawn has left Bernstein without counterplay.

Tuesday 22 September 2020

Chess Evolution: The French Defence (part six)

WORLD champions have a strong influence on opening trends, so Lasker's use of 4.Bg5 against the Classical: 1.e4 e6 2.d4 d5 3.Nc3 Nf6 made a big impression on contemporaries.
He played the move three times in his 1908 world championship match against Tarrasch, scoring two wins and a draw.
Here is their third encounter:
Emanuel Lasker - Siegbert Tarrasch
World Championship 1908 Game 11
French McCutcheon
1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.Bg5
Lasker in his career also played 4.e5, 4.Bd3 and (once) 4.exd5, but the text was overwhelmingly his most-common response to the Classical.
4...Bb4
Tarrasch replied with the McCutcheon in all three games.
5.exd5
Lasker played the somewhat obscure 5.Bd3 in games seven and nine, winning the first but being held to a draw in the second. The main move - then and today - is 5.e5.
5...Qxd5
This active queen recapture is very much in Tarrasch's style of liking piece-play, eg after 1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.e5 Nfd7 in the Steinitz Variation of the French Classical he advocated 5.Nf3 rather than shoring up the centre with 5.f4.
6.Nf3!?
Lasker three times played 6.Bxf6 in his 1907 world championship massacre of Marshall, but 'only' scored a win and two draws (the match finished in Lasker's favour +8=7-0).
6...c5 7.Bxf6 gxf6 8.Qd2
White has given up the bishop-pair but weakened Black's kingside.
8...Bxc3
8...Qd6 was tried in Leonid Totsky (2550) - Sergey Koutsin (2415), Rýmařov (Czechia) 1999, but after 9.a3 Black felt obliged to return the bishop-pair anyway with 9...Bxc3. The further moves 10.Qxc3 Nd7 11.0-0-0 gave White a strong attacking position, according to the analysis engines Stockfish11 and Komodo11.01 (1-0, 26 moves).
9.Qxc3 Nd7?!
The engines much prefer 9...Qe4+, as played by Vidmar in a draw against Leonhardt at the 1906 German chess championship in Nürnberg.
10.Rd1
The engines reckon even stronger is the messy-looking 10.0-0-0!? Qxa2 11.dxc5!? Qa1+ 12.Kd2.
10...Rg8 11.dxc5 Qxc5 12.Qd2
Lasker believes his king will be safer than Black's, and anyway 12.Qxc5?! Nxc5 frees the black position.
12...Qb6 13.c3 a6 14.Qc2 f5!?
Indirectly protecting h7 and creating a possible central outpost square at e4, but weakening the kingside dark squares.
15.g3 Nc5 16.Bg2 Qc7
Planning to fianchetto his remaining bishop.
17.Qe2 b5 18.0-0 Bb7
How should White proceed?
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19.c4!
The white king looks pretty safe, so Lasker seeks to open lines to get at the uncastled black king.
19...b4 20.Qd2 Rb8
Indirectly defending b4 (21.Qxb4?? loses to 21...Bxf3), but now Lasker invades on the kingside.
21.Qh6 Bxf3 22.Bxf3 Qe5
Indirectly defending h7 (23.Qxh7?? loses to 23...Rh8) and attacking b2, but the key to this position is White's better piece-coordination and Black's unsafe king.
23.Rfe1 Qxb2 24.Qf4 Rc8 25.Qd6 f6
This does not help, but there is no way to save Black's position.
26.Bh5+ Rg6 27.Bxg6+ hxg6 28.Rxe6+ 1-0

Monday 21 September 2020

Chess Evolution: The French Defence (part five)

THE move 2.f4 was popular against the French Defence in the first half of the 1800s.
Indeed it was the most-popular move in the 19th century up until 1844, according to games in ChessBase's 2020 Mega database.
But not surprisingly, to modern eyes at least, it was gradually supplanted by 2.d4, thanks to players such as Kieseritzky, Anderssen, Falkbeer and Morphy (although Falkbeer later switched to 2.Nf3).
Once 2.d4 was generally accepted as best, the question then became how to meet 2...d5.
Popular for a long time was the Exchange Variation: 3.exd5, despite London losing with that system against Paris in the 1834 correspondence game that gave the French Defence its name (see part two of this series).
Much of the popularity of the Exchange was due to the successes Paul Morphy had with it, as I covered in the series Morphy v The French.
But gradually the consensus became that Morphy won against the French because he was Morphy, not because the Exchange was particularly powerful.
However it was not until the 1870s that 3.Nc3 really rivalled 3.exd5 and eventually took over from it.
Of the 74 games in Mega20 covering the five years from 1870-74, there are 39 with 3.Nc3, 33 with 3.exd5 and two with 3.Bd3.
There are 82 games covering the five years from 1875-79, with 3.Nc3 featuring in 47 of them compared with 27 for 3.exd5 and eight for 3.e5.
Steinitz, who at one point was more-or-less a lone voice in advocating 2.e5!?, became a leading proponent of 1.e4 e6 2.d4 d5 3.Nc3.
But the lasting legacy of Morphy could be seen in that Steinitz always met the Winawer: 3...Bb4 with 4.exd5. It was another story against the Classical: 3...Nf6.
William* Steinitz - Beniamino Vergani
Hastings 1895
French Steinitz
1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.e5
This line of the Classical is named after Steinitz, but earlier in his career he tried 4.Bg5 and (once) 4.Bd3.
4...Nfd7 5.Nce2!?
Better known is 5.f4, with which Steinitz scored two wins and a draw in Mega20. He played the text in four games, winning them all. The idea is to free the c3 square so the d4 pawn can be supported by a pawn in the likely event of Black playing ...c5.
5...c5 6.c3 cxd4
Much more popular today is 6...Nc6, but the text has been played by Ivanchuk and Short.
7.cxd4 Nc6 8.f4 Bb4+ 9.Nc3
This may have been a novelty. Chigorin and Tarrasch had earlier reached the position after 8...Bb4+ and played 9.Bd2.
9...0-0 10.Nf3 f6 11.a3 Bxc3+ 12.bxc3 a6?!
This looks rather irrelevant to what is going on elsewhere on the board, and does Black's light-square bishop no favours. Komodo11.01 suggests trying to keep lines closed with 12...f5, while Stockfish11 likes 12...Nb6, aiming for the c4 square. Both  engines reckon White is in any case better.
13.a4 Na5 14.Bd3 Qc7 15.Qc2 f5
How should White proceed?
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16.g4
There are plenty of other good moves, but Steinitz's choice illustrates the downside to Black completely closing the centre - Steinitz now feels his king will be perfectly safe standing pat, leaving the king's rook to pressurise along the h file.
16...g6?
This maintains material equality but a better way to do this is 16...Nb6 as the text gives White another target on the kingside.
17.gxf5 exf5
17...gxf5?! opens a file to the black king and so speeds White's attack.
18.h4
White has a kingside attack, with the insurance of a protected passed e pawn in the event of an endgame.
18...Nb6 19.h5 Kg7 20.hxg6 h6
Keeping lines closed in front of the king is Black's best hope, but he is already busted.
21.Qh2 Rh8 22.Qh4 Qd8 23.Ba3 Nc6 24.Qh5 Nc4 25.Nh4!? Nxa3 26.Nxf5+!?
Simpler is 26.Rxa3, but the text also wins.
26...Bxf5 27.Qxf5 Qf8 28.Qd7+ Qe7 29.Qxd5 Rad8 30.Qb3
White regains his piece and will emerge pawns to the good.
30...Rhf8 31.Qxa3 Qxa3 32.Rxa3 Rxf4
The complications are over, and White has emerged two pawns up. The remaining moves were:
33.Ke2 Ne7 34.Rb1 Rd7 35.Rab3 Nd5 36.c4 Rxd4!? 37.cxd5 R4xd5 38.Rxb7 Rxd3 39.e6 Rd2+ 40.Ke1 Rd1+ 41.Rxd1 1-0
*Steinitz changed his first name from Wilhelm to William as part of the process of becoming a US citizen.

Sunday 20 September 2020

Chess Evolution: The French Defence (part four)

EVEN more eccentric-looking than 2.f4 as an answer to the French is Steinitz's 2.e5!?
This is sometimes called the Steinitz Variation, but that invites confusion with the much better-known 1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.e5.
Although 2.e5!? looks eccentric, it served Steinitz well - he scored 79% with the move, according to ChessBase's 2020 Mega database, outperforming his results with 2.d4 by five percentage points.
Wilhelm Steinitz - Szymon Winawer
Vienna 1882
French 2.e5
1.e4 e6 2.e5!?
This game was played in round 12. Winawer was so impressed by Steinitz's novelty, which Steinitz had unveiled in a round-seven win against Bernhard Fleissig, that 18 rounds later - it was a 34-round tournament - Winawer used 2.e5!? to beat Adolf Schwarz.
2...c5
Steinitz and Winawer tied for first in the tournament. They had a play-off match, the first game of which saw Winawer innovate with 2...f6!? 3.d4 c5 4.dxc5!? Bxc5, winning in 27 moves (Steinitz won the second play-off game, after which the players agreed to share the first and second prizes).
3.f4 Nc6
Steinitz - Max Weiss in round 11 saw 3...d5 4.exd6 Bxd6 5.g3 Bd7 6.Nf3 Bc6 with a position that looks at least fine for Black (but 1-0, 35 moves).
4.Nf3 f6
In round 12 James Mason played 4...Nh6 and drew against Bernhard Fleissig, another player apparently impressed by Steinitz's 2.e5!?
5.exf6?!
This seems rather cooperative. After ...
5...Nxf6
... Black has a central pawn-majority and an edge in development.
6.g3 Be7 7.Bg2 Qc7 8.0-0
Position after 8.0-0
8...0-0
8...b6 9.Na3 a6 10.Nc4 Bb7 11.b3 0-0 12.Bb2 b5 13.Ne3 was roughly equal in Steinitz - Celso Golmayo Zúpide, Match (Havana, Cuba) 1883, according to the analysis engines Stockfish11 and Komodo11.01 (but 1-0, 67 moves).
9.Nc3 a6 10.b3 b5 11.Bb2 Bb7 12.d3 Nd8!?
A little unambitious. The engines reckon Black has a good game after 12...Nd4.
13.Qe2 Nf7 14.Nd1!?
Another somewhat-strange knight retreat. There seems nothing wrong with the natural 14.Ne4.
14...Rae8 15.Ne3 Bd8 16.c4 Bc6 17.cxb5 Bxb5 18.a4!?
This is not liked by the engines - presumably because it weakens b3.
18...Bc6 19.Rfc1!?
Wrong rook? Maybe.
19...Qb7!? 20.Nc4!?
Black gets an initiative after 20.Rxc5 Bb6.
20...Bc7 21.Ba3 d6 22.Rab1 a5 23.d4?!
White gets rid of his isolated, but not very weak, d pawn, but the move seems premature.
23...cxd4 24.Kh1
It is possible Stenitz had missed that White is in serious trouble after 24.Nxd4? Bxg2 25.Qxg2 Qa7 with ...e5 to follow.
24...d3!?
The simple 24...e5 may be stronger, but the position is very sharp.
25.Qf1?
White had to play 15.Qd3 Be4 16.Qe2 Bxb1 17.Rxb1, when White's bishop-pair and better-coordinated pieces give decent compensation for the exchange.
25...Ne4?!
Black has an excellent position after 25...e5, eg 26.fxe5 Ng4 27.exd6 Nxd6! with strong play against the white king as 28.Nxd6 Nxd6 29.Bxd6 runs into 29...Rxf3! 30.Bxf3 Bxf3+ 31.Kg1 Qd5.
26.Nd4 Bd5 27.Rb2 e5 28.Nb5 Re6??
The engines' 28...exf4 29.gxf4 Nc5 seems roughly level, but still complicated.
29.Qxd3 Nxg3+ 0-1
Winawer resigned before Steinitz could decide whether to go a piece up by 30.hxg3 or 30.Qxg3. There was no defence, eg 29...Bc6 loses to 30.Nxc7 Qxc7 31.Bxe4.

Saturday 19 September 2020

Chess Evolution: The French Defence (part three)

NOT everyone agreed 2.d4 is White's best reply to 1...e6.
Henry Bird - George Medley
Match (London) 1849
French 2.f4
1.e4 e6 2.f4!?
This may look quaint but it has been played by Carlsen and Nakamura. The main idea is to gain space on the kingside without having to gambit a pawn as would be the case with 1.e4 e5 2.f4.
2...d5 3.e5 c5 4.Nf3 Nc6 5.Bb5
Position after 5.Bb5
Carlsen and Nakamura preferred 5.c3. After the text the position has similarities to the Rossolimo Variation of the Sicilian.
5...Qb6
Medley later preferred 5...Bd7, meeting 6.Bxc6!? with 6...Bxc6.
6.Bxc6+ bxc6!?
Opening a diagonal for the black light-square bishop and reinforcing the black centre, factors that should prove more important than the disruption of Black's queenside pawn-formation. The black queen also gets to continue its pressure against b2. However Black also more-or-less loses the option of castling long.
7.0-0 Nh6 8.Kh1 Be7 9.Nc3 0-0 10.d3 a5!?
Medley judges he is safe enough on the kingside and can get on with queenside play.
11.b3 f6?!
Medley seems to have missed the secondary point of 11.b3, which is not just to prevent Black gaining more space with ...a4. Better is 11...c4!?, preventing 12.Ba3, or 11...Qa7 so 12.Ba3 does not pin the c5 pawn.
12.Ba3 Nf5
Threatens an exchange-winning fork at e3 as well as a defence of the c5 pawn by ...Nd7.
13.Qd2 Ba6 14.exf6 Rxf6 15.Ne5
Now White threatens an exchange-winning fork.
15...Qc7 16.Rae1 Rd8 17.Qf2 Nd4?
Stockfish11 and Komodo11.01 reckon Black's best is 17...c4!? 18.Bxe7 Nxe7, but prefer White after 19.dxc4 or 19.bxc4.
18.Na4 Bb5 19.Bxc5 Bxa4 20.Bxd4 Bb5?
Black had to try 20...c5, but then the engines give 21.Ng4 Rg6 22.Be5, eg 22...Qd7 23.bxa4 Rxg4 24.Rb1 with what they reckon is a winning advantage for White, although there is a lot of play left.
21.Bb6 1-0

Friday 18 September 2020

Chess Evolution: The French Defence (part two)

THIS is the correspondence game that gave the French Defence its name.
London - Paris
Correspondence Match 1834
French Exchange
1.e4 e6 2.d4 d5 3.exd5 exd5
The Exchange Variation has a poor reputation in modern chess, often derided as a would-be drawing weapon by white players afraid of a stronger opponent. Nevertheless it has been played by some very strong whites who were rarely afraid of an opponent - Staunton, Morphy, Kasparov, Kramnik, Carlsen, etc. There is a certain logic to the variation - White's advantage of the move should be easier to exploit in an open position than in a closed one. However the centre after 3...exd5 is better described, in my view, as half-open rather than open.
4.Nf3 Nf6 5.Bd3 c5!?
An aggressive reply that asks whites what they propose to do about the d3 bishop.
6.Qe2+
Most popular is 6.0-0, the point being 6...c4 can be met by 7.Re1+ and 8.Bf1, as in Kasparov (2770) - Korchnoi (2610), Tilburg (Netherlands) 1991. That game continued, after 6...c4 7.Re1+, with 7...Be7 8.Bf1 0-0 9.Bg5 Bg4 10.h3 Bxf3, when Stockfish11 and Komodo11.01 reckon White has a slight edge (1-0, 45 moves).
6...Be7 7.dxc5!?
White scores poorly with this in Mega20, but it has been played by Alexandra Kosteniuk.
7...0-0 8.Be3
Matthew Turner has played this, reaching the position by transposition - Kosteniuk preferred 8.0-0.
8...Re8 9.Bb5?!
This is arguably not in the spirit of the French Exchange. White should probably get on with development, eg 9.Nc3 with the idea of possibly castling long.
9...Nc6 10.Nd4?!
Again White is playing with fire.
How should Black proceed?
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10...Bxc5!
A fine move that perhaps White thought was impossible because of the double attack on c6.
11.Bxc6 bxc6 12.c3
Another non-developing move, but the knight is trapped after 12.Nxc6?? Qc7.
12...Bxd4 13.cxd4 c5
Black gets to play ...c5 for a second time.
14.Qd3
This allows White to capture on d4 in the event of 14...cxd4, which would be the answer to 14.0-0?
14...Qb6 15.0-0 Ba6 16.Qb3
White cannot save the exchange.
16...Qxb3 17.axb3 Bxf1 18.Kxf1 Ng4 19.dxc5 Nxe3+ 20.fxe3 Rxe3 21.Nd2 Rae8 22.b4
Not 22.Rxa7?? Re1+ 22.Kf2 R1e2+ etc.
22...Rd3 23.Rxa7?!
Desperation. The white players realise their game is hopeless with normal play, and so create a pair of passed queenside pawns in the hope of profiting from confusion by their opponents.
23...Rxd2 24.b5 Rxb2 25.b6 d4 26.b7 d3 27.Ra8 Kf8 0-1

Wednesday 16 September 2020

Chess Evolution: The French Defence

HERE I want to give an overview of an opening - namely the French Defence - by looking at how it developed over the centuries.
The French, as is quite well known, is named after a correspondence game between chess clubs in London and Paris.
That was in 1834, when national postal systems were in their infancy, and international mail even more so.
But by then 1...e6 in reply to 1.e4 had been known for more than 200 years, first being published, it seems, in manuscripts of the Italian master Gioachino Greco.
Here is the earliest game in ChessBase's 2020 Mega database
Greco - ??*
Rome (?) 1620
French Advance
1.e4 e6 2.d4 d5 3.e5
I find it interesting that in the first known French Defence, whether a genuine game or not, White should 'play' the Advance Variation (my guess would have been for 3.exd5). The move e5, either here or later, is thematic in that White seeks to take advantage of Black ceding space in the centre and thus on the kingside. It is also quite committal: White is more-or-less obliged to follow up with a kingside attack as otherwise the move e5 will likely prove a tempo expended for no good reason.
3...c5
Attacking the base of White's pawn-chain is second-nature to modern players, but Joseph Blackburne experimented in 1885 with attacking the head of the pawn-chain with 3...f6!?, drawing with Max Weiss and George Mackenzie.
4.c3 cxd4!?
This is generally regarded today as premature, not least because it allows White to clear the c3 square for the white queen's knight. However it has appeared in computer games and was played in 1981 by Bulgarian international master, and future grandmaster, Krum Georgiev (but the game was agreed drawn in 10 moves, so perhaps the players were peacefully inclined from the start).
5.cxd4 Bb4+
Patzer sees check, patzer plays check (or, probably in this case, is made to play a check by the game's composer). Strong players who have reached the position after 5.cxd4 by transposition, eg Francisco Vallejo Pons and Ruifeng Li, have generally preferred 5...Nc6. In their cases the games - one by Pons, two by Li - went 1.e4 c5 2.c3 e6 3.d4 cxd4 4.cxd4 d5 5.e5. All three games were won by Black.
6.Nc3 Bxc3+!?
Black gives up his good bishop to saddle White with a backward pawn on a half-open file. But the pawn on c3 will support White's centre and should not be difficult to defend.
7.bxc3 Nc6 8.Bd3
8.Qg4 is at least as strong.
8...Nge7 9.f4
9.Ne2 was played by a 2265 in a Hungarian game in 1994. The text is often played by White in this type of pawn-structure.
9...Nf5 10.Nf3
How should Black proceed?
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10...0-0?
Black's play has been reasonable up to this point. The analysis engines Stockfish11 and Komodo11.01 reckon White only has a slight edge after 10...Na5, targeting the c4 square. The text, although plausible at first glance, is an example of "castling into it."
11.g4 Nh4 12.0-0 Nxf3+
The best alternative the engines can come up with is 12...f5 13.exf6 Nxf3+ 14.Qxf3 gxf6, but reckon White has a winning attack after 15.Qh3.
13.Qxf3 Bd7?!
Black had to gain some breathing room on the kingside, eg 13...f5 14.exf6 Qxf6, but White keeps a large advantage.
14.Qh3 g6 15.f5 exf5 16.gxf5 gxf5 17.Rxf5!?
Objectively not best, according to the engines, but it leads to an instructive finish.
17...Bxf5
The engines give best play as 17...Kh8 18.Kh1 Ne7 19.Bg5 f6 20.Bxf6+ Rxf6 21.exf6 Bxf5 22.Bxf5 Nxf5 23.Qxf5, when White is only a pawn up but is completely winning.
18.Bxf5 1-0
*Many of Greco's recorded 'games' are thought to have been composed by him for instructional purposes rather than being genuine over-the-board encounters, and that is probably the case with this example.
(To be continued)

Diced Chess (part two)

MY friend Tim Johnson insisted on an immediate rematch, and I was very happy to oblige.
As with the first game of Diced Chess, I will write light notes as the game goes along.
Spanton - Tim Johnson
1.(KP)d4 (QN)Nf6 2.(RR)Bg5
A Trompowsky! I am hoping to capture on f6 and withdraw the bishop to safety.
2...(NP)Ne4
The drawback with 2.Bg5 - at least at Diced Chess.
3.(KQ)Qd3 (BN)Nxg5 4.(RN)Nf3 (RP)e6!
As TJ observed, this gives some cover to the king's knight as well as opening diagonals for the king's bishop and queen.
5.(NN)Nxg5 --
Capturing a piece and getting to roll again as I moved with the piece doubly indicated by the dice.
6.(QQ)Qf3 --
Threatening mate and again forcing my opponent to skip a turn.
7.(RR)Qxf7#
The final position - perhaps my awarding an exclamation mark to Black's fourth (and last) move was too kind
Well, that was short but sweet (from my viewpoint). However, even I am forced to admit I was a trifle lucky with the dice.
If nothing else, the shortness of this game makes a big contrast to our first game.
Here is the game inputted to ChessBase: 1. d4 Nf6 2. Bg5 Ne4 3. Qd3 Nxg5 4. Nf3 e6 5. Nxg5 -- 6. Qf3 -- 7. Qxf7#
I believe I can now justly claim to be the undisputed champion of Diced Chess.

Tuesday 15 September 2020

Diced Chess

QUITE a few years ago - possibly in the 1990s - I bought a game called something like Chuck-a-Chess.
It consisted of a number of normal six-sided dice, except that each face was covered by a chess piece* rather than a number of dots.
Unfortunately I threw the dice out during one of my periodic clear-outs, and have been unable to find a replacement set.
So instead I have invented my own game, and called it Diced Chess.
To play you need two ordinary dice (as well as a chess set and board) and the ability not to turn the board over when luck goes outrageously against you.
In Diced Chess the six faces on a die represent the six pieces: 6=K, 5=Q, 4=R, 3=B, 2=N, 1=P.
The player whose move it is rolls the two dice and may make any legal move with either of the two pieces indicated by the dice.
Rolling a double lets the player move any piece. If the piece moved is the one indicated by the dice, eg two 5s would mean a queen, the opponent has to skip a turn, unless the move played resulted in a check.
To castle you need to roll either a 6, for a king, or a 4, for a rook, or a double.
A player in check gets up to three rolls of the dice to escape check or else forfeit the game.
Stalemate only counts if the player with no legal moves, and so in a stalemate situation, makes a roll that results in a number that represents one of his surviving pieces, or rolls a double.
Clearly there will be times when a player rolls numbers that do not allow a move, in which case the turn passes to the opponent. However a player may never deliberately pass.
What follows is the very first game of Diced Chess, played against my friend Tim Johnson. He won the draw for colours and so had white.
Tim Johnson - Spanton
In the notation the letters in brackets show what the player rolled with the dice, the numbers translated for convenience's sake into chess pieces. So TJ's first roll below resulted in a 5 and a 1, which are represented as QP.
I will write light notes as the game goes along.
1.(QP)e4 (QR)--
A null move straight off - not a good start for me.
2.(RR)d4 (RR)c5 3.(QP)dxc5
TJ said he was tempted to play Nakamura-style with 3.Qh5!?, but feared the queen would be vulnerable.
3...(BN)Nf6 4.(RR)Bg5 (KP)h6 5.(KB)Bxf6 (RB)Rg8
This is arguably worse than a null move.
6.(BN)Bd4 (KP)e5!?
Taking a risk to try to reduce my material deficit.
7.(BN)Bxe5 (KR)Rh8 8.(RN)Nf3 (BP)Bxc5 9.(QP)Qd5!
A strong move as the queen radiates threats from d5 without being very vulnerable.
9...(QN)Qa5+
Going for broke. White now gets up to three rolls of the dice to escape check.
10.(KR)Kd1
Not a move he would have wanted to play. It will be interesting to see how vulnerable the white king is in the centre.
10...(QP)Qb6 11.(QR)Qb3!?
11.Qxc5!? is a gamblers' move.
11...(QN)Qxb3
Showing the downside to White's 11th move - will the black queen successfully hit and run?
12.(QR)Rg1 (NP)Nc6 13.(QB)Bxg7 (RP)Rg8 14.(RB)Bxh6 (PP)Qxb2 15.(BB)Bc1!? (QR)Qxa1
It is becoming a massacre, but a game of Diced Chess ain't over till it's over.
16.(RB)Bb2!?
Doggedly going after the black queen.
16...(KR)Rg4 17.(QB)Bxa1
White's strategy has worked - material is now roughly equal.
17...(QR)Rxe4 18.(QR)Rh1 (KK)Bxf2!?
Materialistic. Moving the d pawn to open a diagonal for the light-square bishop was also tempting.
TJ here rolled a 4 and a 3. What would you play?
*****
*****
*****
*****
*****
19.(BN)Bd3!
A good move that attacks a black piece and provides extra defence against an attempt to mate by ...Re1+, as now the white rook at h1 gives additional cover to the e1 square.
19...(KQ)Kf8 20.(KQ)Kd2 (KN)Nb4 21.(QR)Rf1 (QR)Re6 22.(QR)Rxf2
White has clawed his way back to a material advantage.
22...(QB)--
The second time I have been unable to move.
23.(RR)Bc3
Threatening to make a capture with check.
23...(RN)Nxd3 24.(QQ)cxd3 (RN)Rb6!
Threatening the queen's knight but also providing extra cover against a check from b4.
25.(RB)Rf1 (PP)Rxb1 26.(KP)Kc2 (KK)Rxf1
The tide has turned again, but possibly not decisively.
27.(KB)Bb4+
This must be worth a try, even though the odds favour me rolling a 6 or a 1 in six tries (three rolls of two dice) ...
27...(NN)Kg8
... or indeed a double.
28.(RB)Bd6!? (QN)-- 29.(NN)Nd2
White gets to roll again as he moved a piece indicated by the doubled dice.
29...-- 30.(KP)h4 (KQ)Kh7
Keeping off the dark squares.
31.(BN)Nxf1 (KN)Kg8
Safety first.
32.(BN)Ne3 (BP)b6 33.(QR)--
White's first null move.
33...(RP)a6 34.(NP)Nd5 (KB)Bb7 35.(KR)Kc3 (KB)Bxd5 36.(BB)Kd4 (KQ)Kh7 37.(KP)Kxd5 (RP)Rg8 38.(KQ)Ke5 (QB)-- 39.(KN)Kf5 (QR)Rxg2
I was also tempted by 39...Rg6, but decided to take a pawn that could provide part of a mating net.
40.(RN)-- (RN)Rxa2 41.(KB)Kf6 (KB)Kg8 42.(KN)Ke7 (BN)-- 43.(NP)h5 (KP)Kh7!? 44.(KQ)Kxf7  (NN)Rf2+ 45.(QR)(KP)Ke7 (QP)a5 46.(RP)d4 (BN)-- 47.(BN)Bg3 (RB)Rf3 48.(RR)Bc7 (KK)a4!?
I could have played 48...Kh6!? and rolled again, but did not want to tempt fate by putting my king on a dark square.
49.(KN)Kxd7 (QP)a3 50.(BN)Bxb6 (KN)Kg8 51.(QB)Bc5 (RB)Rf7+ 52.(QQ)Ke6 (PP)a2
A very fortunate roll of the dice as I get to move a pawn to the seventh rank and roll again.
53.-- (BN) 54.(RN)-- (KR)Rh7 55.(KN)Kd5 (QB)-- 56.(RB)Bb4 (PP)a1=Q
Another great roll for me.
57.-- (RB)Rxh5+
TJ offered to resign here, but we agreed to play on - just in case something really weird happens.
58.(QQ)Ke6 (QP)Qxd4 0-1
But now TJ did resign as Black must win - a game of fluctuating fortunes.
*I am using 'piece' in its non-technical sense to include pawns.

Monday 14 September 2020

First Tube Puzzle Of 2020

I MISSED out on public transport during the lockdown and I have had precious few reasons - no league chess to go to, for instance - for using it since.
But recently I saw the following serial number on a Northern Line train: 51578.
As usual, each number should be used once, and once only, and must be added, subtracted, multiplied or divided to make a balanced equation.
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
Clue: there is a perfect solution, ie a solution that uses each number in order.
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
*****
My solution:  5 x 1 (÷ 5) + 7 = 8

Sunday 13 September 2020

Champion Of Champions: Challenge

VLADIMIR Kramnik won my Champion Of Champions tournament, in which the 16 classical world champions faced off in a knockout format.
'Games' were decided by choosing each player's most-popular move in any given position in ChessBase's 2020 Mega database.
There is no reason why such an event should be restricted to world champions - anyone can take part as long as there is a reasonable number of a player's games in Mega20.
I have 923 games in Mega20, so here I will be taking on the Champion Of Champions in a two-game match.

Vladimir Kramnik - Spanton
Pseudo-Chigorin
1.d4 d5 2.Nf3!?
There are 157 games with this move by Kramnik in Mega20, compared with 152 for 2.c4.
2...Nc6!?
Kramnik has not faced this move, so this is as far as we can go
The analysis engines Stockfish11 and Komodo11.01 give White an averaged advantage of +57.5, which means I have it all to do in the next game.

Spanton - Vladimir Kramnik
Spanish Four Knights Rubinstein
1.e4 e5 2.Nf3 Nc6 3.Bb5 Nf6 4.Nc3 Nd4
I have not faced Rubinstein's 4...Nd4 in Mega20, so again the 'game' comes to a quick conclusion
The analysis engines give me an averaged advantage of +25.5 - not bad, but not enough to overcome Kramnik's game-one advantage.
So Kramnik wins with a score of +32 - closer than I feared.

Saturday 12 September 2020

Champion Of Champions (part 15)

HERE is the tournament bracket ahead of the final.

Round of 16               Quarter-Finals          Semi-Finals                      Final
1. Steinitz
v----------------------------Carlsen
16. Carlsen (+102.5)
                                    v................................Tal
8.Tal (+8.5)
v----------------------------Tal (+79.5)
9.Petrosian
                                                                      v.....................................Botvinnik
6. Botvinnik (+66)
v----------------------------Botvinnik (+18.5)
11. Fischer
                                    v.................................Botvinnik (+406.5)
13. Kasparov
v----------------------------Alekhine
4. Alekhine (+21.5)
                                                                                                             v...........................
3. Capablanca
v----------------------------Kramnik (+118)
14. Kramnik (+12)
                                     v................................Kramnik (+13)
5. Euwe
v----------------------------Karpov
12. Karpov (+11.5)
                                                                       v.....................................Kramnik
7. Smyslov (+18)
v----------------------------Smyslov (+11.5)
10. Spassky
                                     v................................Smyslov
15. Anand
v----------------------------Lasker
2. Lasker (+50.5)

Botvinnik reached the final by beating Fischer, Alekhine and Tal; Kramnik reached the final by beating Capablanca, Karpov and Smyslov.
Who had the tougher route? Hard to say, but Botvinnik's margins of victory were, in general, more convincing.

Final
Game One
Mkikhail Botvinnik - Vladimir Kramnik
Nimzo-Indian
1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.e3 0-0 5.Bd3 c5
Kramnik has played this eight times in ChessBase's 2020 Mega database, compared with five times for 5...d5.
6.a3
This is as far as we can go as Kramnik has not faced 6.a3
The analysis engines Stockfish11 and Komodo11.01 are divided over this position, with the former liking Black but the latter narrowly preferring White.
Their averaged evaluations give Kramnik a score of +25.5 - a commanding position since he has the white pieces to come.

Game Two
Vladimir Kramnik - Mikhail Botvinnik
Queen's Indian
1.d4 Nf6 2.c4 e6 3.Nf3 b6 4.g3 Bb7 5.Bg2 Be7 6.0-0 0-0 7.Re1 d5 8.cxd5
As far as we can go - Botvinnik did not face 8.cxd5
The engines give White an averaged advantage of +11.
Here is the final tournament bracket.

Round of 16               Quarter-Finals          Semi-Finals                      Final
1. Steinitz
v----------------------------Carlsen
16. Carlsen (+102.5)
                                    v................................Tal
8.Tal (+8.5)
v----------------------------Tal (+79.5)
9.Petrosian
                                                                      v.....................................Botvinnik
6. Botvinnik (+66)
v----------------------------Botvinnik (+18.5)
11. Fischer
                                    v.................................Botvinnik (+406.5)
13. Kasparov
v----------------------------Alekhine
4. Alekhine (+21.5)
                                                                                                             v.............................Kramnik
3. Capablanca
v----------------------------Kramnik (+118)
14. Kramnik (+12)
                                     v................................Kramnik (+13)
5. Euwe
v----------------------------Karpov
12. Karpov (+11.5)
                                                                       v.....................................Kramnik (+36.5)
7. Smyslov (+18)
v----------------------------Smyslov (+11.5)
10. Spassky
                                     v................................Smyslov
15. Anand
v----------------------------Lasker
2. Lasker (+50.5)

The Champion Of Champions: Vladimir Kramnik.

Friday 11 September 2020

New ECF RATINGS Are Out

THE English Chess Federation is switching from three-figure grades to four-figure ratings, which will be compatible with Fide elo ratings.
The switch means my ECF grade of 173 is replaced with an ECF rating of 1998, which is a straight conversion using the formula ECF x 7.5 (+700).
So the introduction near the top of my blog now reads:
"I begin this blog after getting back into league chess following many years' absence due to work. My post-job status also means I am able to play more tournament chess. My new club in London is Battersea and my first game for them is on Thursday September 14, 2017. I start with a Fide rating of 1858 and an ECF grade of 169 (=1968 elo). My latest Fide rating (Sep 2020) is 1813; my latest ECF rating (Aug 2020) is 1998."
As can be seen, my ECF rating is considerably different - 185 points - from my Fide rating.
ECF ratings, like Fide ones, should now be updated monthly.

Champion Of Champions (part 14)

HERE is the updated tournament bracket after the first semi-final.

Round of 16               Quarter-Finals          Semi-Finals                      Final
1. Steinitz
v----------------------------Carlsen
16. Carlsen (+102.5)
                                    v................................Tal
8.Tal (+8.5)
v----------------------------Tal (+79.5)
9.Petrosian
                                                                      v.....................................Botvinnik
6. Botvinnik (+66)
v----------------------------Botvinnik (+18.5)
11. Fischer
                                    v.................................Botvinnik (+406.5)
13. Kasparov
v----------------------------Alekhine
4. Alekhine (+21.5)

3. Capablanca
v----------------------------Kramnik (+118)
14. Kramnik (+12)
                                     v................................Kramnik
5. Euwe
v----------------------------Karpov
12. Karpov (+11.5)
                                                                       v.....................................
7. Smyslov (+18)
v----------------------------Smyslov (+11.5)
10. Spassky
                                     v................................Smyslov
15. Anand
v----------------------------Lasker
2. Lasker (+50.5)

Semi-Finals
Match Two: Kramnik v Smyslov
Game One
Vladimir Kramnik - Vasily Smyslov
Bogo-Indian
1.d4 Nf6 2.c4 e6 3.Nf3 Bb4+
There are 41 examples of Smyslov playing the Bogo-Indian in ChessBase's 2020 Mega database, compared with 40 for the Queen's Indian: 3...b6.
4.Bd2
Five examples of Kramnik playing this compared with four for 4.Nbd2.
4...a5
This is as far as we can go as Kramnik has not faced 4...a5 in Mega20
The analysis engines Stockfish11 and Komodo11.01 give White an averaged advantage of +47.5

Game Two
Vasily Smyslov - Vladimir Kramnik
Spanish Berlin
1.e4 e5 2.Nf3 Nc6 3.Bb5 Nf6 4.0-0 Nxe4 5.Re1 Nd6 6.Nxe5 Be7
We have reached exactly the same position as in game one of the quarter-final Smyslov - Lasker, which had to be called here as Smyslov did not face 6...Be7
White's advantage in this position, according to the averaged evaluations of Stockfish11 and Komodo11.01, is 34.5 - not enough for Smyslov to overturn Kramnik's score in the first game of this semi-final.
Here is the updated tournament bracket.

Round of 16               Quarter-Finals          Semi-Finals                      Final
1. Steinitz
v----------------------------Carlsen
16. Carlsen (+102.5)
                                    v................................Tal
8.Tal (+8.5)
v----------------------------Tal (+79.5)
9.Petrosian
                                                                      v.....................................Botvinnik
6. Botvinnik (+66)
v----------------------------Botvinnik (+18.5)
11. Fischer
                                    v.................................Botvinnik (+406.5)
13. Kasparov
v----------------------------Alekhine
4. Alekhine (+21.5)

3. Capablanca
v----------------------------Kramnik (+118)
14. Kramnik (+12)
                                     v................................Kramnik (+13)
5. Euwe
v----------------------------Karpov
12. Karpov (+11.5)
                                                                       v.....................................Kramnik
7. Smyslov (+18)
v----------------------------Smyslov (+11.5)
10. Spassky
                                     v................................Smyslov
15. Anand
v----------------------------Lasker
2. Lasker (+50.5)

Thursday 10 September 2020

Champion Of Champions (part 13)

HERE is the updated tournament bracket ahead of the semi-finals.

Round of 16               Quarter-Finals          Semi-Finals               Final
1. Steinitz
v----------------------------Carlsen
16. Carlsen (+102.5)
                                    v................................Tal
8.Tal (+8.5)
v----------------------------Tal (+79.5)
9.Petrosian
                                                                      v...............................
6. Botvinnik (+66)
v----------------------------Botvinnik (+18.5)
11. Fischer
                                    v.................................Botvinnik
13. Kasparov
v----------------------------Alekhine
4. Alekhine (+21.5)

3. Capablanca
v----------------------------Kramnik (+118)
14. Kramnik (+12)
                                     v................................Kramnik
5. Euwe
v----------------------------Karpov
12. Karpov (+11.5)
                                                                       v...............................
7. Smyslov (+18)
v----------------------------Smyslov (+11.5)
10. Spassky
                                     v................................Smyslov
15. Anand
v----------------------------Lasker
2. Lasker (+50.5)

Semi-Finals
Match One: Tal v Botvinnik
Game One
Mikhail Tal - Mikhail Botvinnik
French Tarrasch
1.e4 e6 2.d4 d5 3.Nd2
As noted in part two of this series. when Tal 'played' Petrosian, there are 49 examples of Tal choosing 3.Nd2 in ChessBase's 2020 Mega database, compared with 46 examples of the arguably more Tal-like 3.Nc3.
3...c5 4.Ngf3 Nc6
Botvinnik played this once and 4...a6 once, but lost with the latter and won with the former, so 4...Nc6 is chosen on tiebreak.
5.exd5
Tal played this and 7.Bb5 seven times each, in both cases scoring 79%, but his rating performance was much better with the text.
5...exd5 6.Bb5 cxd4
Botvinnik played this and 6...Bd6 twice each, scoring 50% with the latter but a win and a draw with the text.
Tal did not face 6...cxd4, so this is as far as we can go
The analysis engines Stockfish11 and Komodo11.01 give Tal an averaged advantage of +52.5 - a large score for Botvinnik to overcome.

Game Two
Mikhail Botvinnik - Mikhail Tal
Nimzo-Indian
1.d4 Nf6 2.c4 e6 3.Nc3 Bb4
There are 81 games in Mega20 in which Tal played the text, compared with 10 for 3...c5. He scored much better with the latter, but moves are chosen for 'games' in Champion Of Champions by popularity, not success.
4.e3 0-0 5.Bd3 d5 6.a3 dxc4 7.Bxc4 Bd6 8.Nf3 Nc6 9.b4 e5 10.Bb2 Bg4 11.d5
Botvinnik played the text and 11.dxe5 once each, drawing with the latter but winning with 11.d5.
11...Ne7 12.h3 Bd7 13.Ng5 Ng6 14.Ne6 fxe6 15.dxe6 Kh8 16.exd7 Qxd7 17.0-0 Qf5 18.Nd5 Ng8 19.Qg4 Qc2 20.Qe2 Qf5 21.Qg4 Qc2 22.Qe2 Qf5 23.e4 Qd7 24.Rad1 Rad8 25.Qg4 Qe8 26.g3 Nh6 27.Qh5 Ng8 28.Qe2 N6e7 29.Ne3 Nh6 30.Ng4 Nxg4 31.hxg4 Nc6 32.Kg2 Be7 33.Bd5 Nd4 34.Bxd4 exd4 35.Bc4 c5 36.b5 Bf6 37.f4 d3 38.Rxd3 Rxd3 39.Bxd3 Bd4 40.e5 g6 41.Rh1 Kg7 42.Qe4 b6 43.Bc4
We have reached the final position - Tal resigned here - of  the third game from the Botvinnik-Tal world championship match of 1961
The engines give White an averaged advantage of +459, meaning Botvinnik has well and truly overcome his 52.5 deficit from game one.
Here is the updated tournament bracket.

Round of 16               Quarter-Finals          Semi-Finals                      Final
1. Steinitz
v----------------------------Carlsen
16. Carlsen (+102.5)
                                    v................................Tal
8.Tal (+8.5)
v----------------------------Tal (+79.5)
9.Petrosian
                                                                      v.....................................Botvinnik
6. Botvinnik (+66)
v----------------------------Botvinnik (+18.5)
11. Fischer
                                    v.................................Botvinnik (+406.5)
13. Kasparov
v----------------------------Alekhine
4. Alekhine (+21.5)

3. Capablanca
v----------------------------Kramnik (+118)
14. Kramnik (+12)
                                     v................................Kramnik
5. Euwe
v----------------------------Karpov
12. Karpov (+11.5)
                                                                       v...............................
7. Smyslov (+18)
v----------------------------Smyslov (+11.5)
10. Spassky
                                     v................................Smyslov
15. Anand
v----------------------------Lasker
2. Lasker (+50.5)