Showing posts with label Danish Gambit. Show all posts
Showing posts with label Danish Gambit. Show all posts

Thursday, 10 February 2022

Something Rotten In The State Of The Danish

IT is not surprising analysis engines have detected many tactical errors in the analyses of the old masters.
Modern engines sometimes find incredible resources and rarely, if ever, make short-term tactical miscalculations in middlegames (their opening and endgame skills are not at such a high level, however).
Occasionally I come across an old game where instinctively I disagree with, or at least find surprising, the positional conclusions of the annotator(s).
Usually I am the one who is mistaken, which is why I will be particularly interested in what Stockfish14.1 and Komodo12.1.1 have to say about the following from 500 Master Games Of Chess.
The algebraicised notes in italics are by Savielly Tartakower and Julius du Mont.

Jacques Mieses - Mikhail Chigorin
Deutscher Schachbund (Hannover) 1902
Danish Gambit
The exciting vicissitudes of this game can be divided into three phases, from the point of view of Black: stopping the enemy's first onslaught; building up a close but defendable position; watching all openings, and, at the right moment, launching the counterattack.
1.e4 e5 2.d4 exd4 3.c3 dxc3 4.Bc4 cxb2 5.Bxb2 Qe7?!
This defence is not without logical foundation. The queen surveys the critical sector, prepares for casting on the queenside, and in addition threatens to win one of the bishops by 6...Qb4+.
The engines are distinctly unimpressed, preferring 5...Nf6, which was an earlier favourite of Chigorin's and has been played by Magnus Carlsen, and 5...Bb4+, which Tartakower and du Mont describe in analysis to another game as "not as promising as it looks."  It is possible 5...Qe7?! was a novelty - there is no earlier example in ChessBase's 2022 Mega database. The move immediately struck me as suspicious as it slows Black's kingside development, but perhaps this is not important if the black king finds safety on the queenside.
6.Nc3 c6!?
This defends the b5 and d5 squares from a knight incursion and prepares the tempo-gaining ...d5.
7.Qc2
Two years later, against the same opponent at Cambridge Springs, Pennsylvania, Mieses played 7.Nge2!? The game continued 7...b5!? (7...Qb4 can be countered by 8.Bb3) 8.Bb3 a5 9.Rc1!? Na6 10.0-0 Nc5?! 11.Nd4 Nxb3 12.Nf5!? Qe6 13.axb3, after which the engines reckon White has much more than enough compensation for two paws (but 0-1, 54 moves).
7...d6
Suicidal would be 7...d5 8.Bxd5 cxd5 9.Nxd5 and wins.
The engines prefer 7...d5!? to the text, as long as Black does not grab the bishop, eg 8.Bxd5 Nf6 9.Bb3 Na6, when Stockfish14.1 gives White a slight edge although Komodo12.1.1 calls the position equal.
8.0-0-0?!
The engines reckon this is a mistake, preferring 8.Nf3 Be6 9.Bxe6 fxe6 10.Rd1!?, when they rate White as having full compensation for being two pawns down.
8...Be6
How should White proceed?
*****
*****
*****
*****
*****
9.Be2!?
At the crossroads. Instead of giving up territory, the imaginative 9.Nd5 maintains the initiative.
The authors do not explain how White should continue after 9...cxd5, eg 10.exd5 Qg5+ and ...Bf5, or 10.Bb5+ Nd7 11.exd5 Qg5+ etc. The engines reckon objectively best is 9.Bxe6, but it is understandable Mieses thought such an exchange would help Black's defence.
9...Nd7 10.Nf3 Nc5
Not 10...0-0-0 as yet, because 11.Qa4 and White gets going.
The engines reckon castling is fine, and if 11.Qa4 then 11...Kb8.
11.Rd4 0-0-0 12.Rhd1 Qc7
Slowly but surely Black proceeds with his development. 12...Nf6 would be premature, on account of 13.e5.
The engines prefer 12...Nf6 to the text, meeting 13.e5 with 13...Ne8 or 13...Nd5, in each case claiming a winning advantage for Black.
13.Na4 Nd7!? 14.R1d3?!
This natural-looking move makes White's position worse, according to the engines, although their suggestion of 14.Bc4!? Bxc4 15.Rxc4 Ngf6 16.Kb1 hardly inspires. It seems White has nowhere near enough compensation for being two pawns down.
14...Ngf6 15.Rc3 Be7
The "hedgehog" position, which Black has obtained, is cramped but solid, his pawns being particularly strong in the defence of the king's position.
16.Rb4
With the threat of 17.Ba6, which is, however, prevented by Black's next move.
The point being 17.Ba6 bxa6 is met by 18.Rxc6.
16...Nb8
Also meeting the threat are 16...Nc5 and 16...c5.
17.Nd4 d5
This counterthreat in the centre provokes the crisis.
18.Nxc6!?
Being already two pawns to the bad, and threatened with the loss of a third, White, by the offer of the knight, tries to alter the normal course of things.
18...Nxc6 19.Ba6
How should Black proceed?
*****
*****
*****
*****
*****
19...Qf4+
As neither 19...Kb8 20.Rxc6, nor 19...Kd7 20.Rxb7, nor 19...bxa6 20.Rxc6, nor 19...Nxb4 20.Rxc7+, nor, finally, 19...Bd7 20.Bxb7+, is admissible, the "relieving check" in the text is the only move, which, however, saves the situation and refutes the hostile combination.
The engines show 19...Kb8? 20.Rxc6? loses to 20...Qf4+ 21.Kb1 Bxb4. However they reckon 20.Rxb7+ Qxb7 21.Rxc6 leads to a draw by repetition after 21...Qb4 22.Bc3 Qa3+ 23.Bb2 Qb4 etc. They also reckon Black is better after 19...Bd7? 20.Bxb7+? Qxb7 21.Rxb7 Kxb7, but that White wins with 20.Rxb7, eg 20...Qxb7 21.Rxc6+.
The authors do not mention 19...Bxb4?, which the engines reckon leads to equality after 20.Rxc6 Ne8!? 21.Bxg7!?, eg 21...Ba3+ 22.Nb2 Rg8 23.Rxc7+ Nxc7 24.Be5 Bd6 25.Qc6 Bxe5 26.Qxb7+ Kd7 27.Nd3! Bd6 28.Bb5+.
20.Re3
Or 20.Kb1 Bxb4 21.Rxc6+ Kb8, and the whole of White's game collapses.
20...Bxb4 21.Qxc6+ Qc7 22.Bxb7+ Kb8 23.Be5
His final trump.
23...Qxe5 24.Rb3 Qc7 0-1

Thursday, 13 January 2022

Gem Of A Game

FROM time to time I go through Tartakower & du Mont's 500 Master Games Of Chess.
Here is an especially sparkling game that caught my attention.
Notes in italics are algebraicised from the book.

Julius Perlis - Joseph Blackburne
Ostend Masters 1907
Danish Gambit
1.e4 e5 2.d4 cxd4 3.c3!?
There are almost 5,000 examples of this move in ChessBase's 2022 Mega database, with White scoring a respectable 55%.
3...d5!?
This reply reduces White's score to 48%, whereas accepting the gambit with 3...dxc3, which has been played by Magnus Carlsen, results in White scoring 58%.
4.exd5 Qxd5 5.cxd4 Nc6 6.Nf3 Bg4!?
This game was played in round 22(!), whereas 18 rounds earlier Jacques Mieses - Blackburne saw 6...Nf6 7.Nc3 Bb4 8.Be2 Ne4 9.Bd2 Bxc3 10.bxc3 0-0 11.0-0 Bg4 12.Be1!?, when Black's lead in development probably neutralises White's bishop-pair (but 1-0, 37 moves).
7.Be2
How should Black proceed?
*****
*****
*****
*****
*****
7...Nf6
Here the novice should avoid the frightful blunder 7...Bxf3 8.Bxf3 Qxd4 9.Bxc6+, and Black loses the queen.
8.0-0
Better is 8.Nc3, and if either 8...Bb4 or even 8....Qa5 [then] 9.0-0. If 8...Qh5 [then] 9.h3.
My main analysis engines Stockfish14.1 and Komodo12.1.1 reckon 8...Qd7 is an adequate response to 8.Nc3.
8...Bd6!?
Black preserves the option of castling on either wing.
The engines strongly dislike the text, preferring 8...Qd7 or 8...0-0-0.
9.Nc3 Qh5!?
This is also doubtful, according to the engines, which prefer 9...Qf5 or 9...Qa5.
10.Re1
This is enough for an advantage, but even stronger, according to the engines, is 10.h3, which had been played the previous year by Paul Leonhardt, albeit in a loss to Rudolf Spielmann.
10...0-0 11.h3
Now that White is definitely threatened with 11...Bxf3 followed by ...Qxh2[+] it is for him a choice of evils, namely either the text move or 11.g3, which equally weakens the king's position, or 11.Ne5, which loses material by reason of 11...Nxe5 12.dxe5 Bxe5 13.h3 (or 13.Bxg4 Bxh2+, followed by ...Nxg4 , with an advantage of two pawns) Bxe2 14.Qxe2 Qxe2 etc, and Black has the better game.
The engines agree with much of this analysis, but disagree that the text is weakening.
What should Black play?
*****
*****
*****
*****
*****
11...Rad8?!
The beginning of a grand combination.
Unfortunately the combination is almost certainly faulty. Best, according to the engines, is 11...Bxf3 12.Bxf3 Qf5, when White seems to have a good IQP position.
12.hxg4 Nxg4
How should White proceed?
*****
*****
*****
*****
*****
13.Bg5?
Correct, according to the engines, is 13.g3, eg 13...Nxd4 14.Nh4! Nxe2+ 15.Qxe2 Bc5 16.Be3 or 13...Rfe8 14.Nh4! Nxd4 15.Kg2 Nxe2 16.Rxe2. Less clear is 13.Be3, although both 13...Bh2+ 14.Kf1 Be5! 15.Bd3 and 13...Rfe8 14.Bd3 Bh2+ 15.Kf1 seem good for White.
13...Bh2+ 14.Kf1 Be5! 15.Bd3?!
If 15.Bxd8 there is the beautiful combination 15...Qh1+ 16.Ng1 Nh2#.
But probably better than the text is the engines' 15.Kg1, when 15...Bxd4 16.Ne4 f5 17.Bf4 fxe4 18.Nxd4 leads to complicated play, eg 18...Rxf4 19.Qb3+ Rd5 20.Bxg4 (20.Qg3+!?) Nxd4 21.Bxh5 Nxb3 22.axb3 Rxh5 23.g3! Rg4 24.Rxa7, which results in a double-rook-and-pawn ending that is clearly good for Black but not necessarily winning.
15...Rxd4?
Missing a win by 15...Qh1+ 16.Ke2 Qxg2, eg 17.Kd2 Nxf2 or 17.Rf1 Nxd4+ 18.Nxd4 Rxd4 19.Qd2 Re8 20.Kd1 Rxd3! 21.Qxd3 Bxc3 22.bxc3 Nxf2+.
16.Nxe5?
If 16.Nxd4 [then] 16...Nxd4, cutting off the king's retreat, but clearly not 16...Qh1+ 17.Ke2 Nxd4+ 18.Kd2 etc.
The engines give 16.Bh4, eg 16...Nh2+ 17.Nxh2 Qxh2 18.Re3!
16...Re8?
Another quiet move, but how powerful! It needs, however, a great deal of self-possession to make such a move when, temporarily, two pieces down. Of far less value would be the plausible continuation 16...Ncxe5 17.Rxe5 Rxd3 18.Qxd3 Bxe5 19.Qg3 Qh1+ 20.Ke2 Qxa1 21.Qxe5 Qxb2+ 22.Kf3 and the fight would still be an open one.
The engines reckon the above line greatly favours Black after 22...Qb6 or 22...f6. But even better, according to them, is 16...Qh1+ 17.Ke2 Qxg2, eg 18.Be3 Ngxe5 19.Bxh7+ Kxh7 20.Bxd4 Qg4+, as 21.Kf1 runs into 21...Nf3 22.Re4 Qg1+ 23.Ke2 Ncxd4+.
17.Re4 Rxe4 18.Bxe4 Ncxe5 19.Bf4 Ng6 20.Bg3 Qh1+ 21.Ke2 Qxg2
What should White play?
*****
*****
*****
*****
*****
22.Qh1?
The strongest resistance would result from 22.Qd4 Nf6 23.Kd3.
The engines continue the above line with 23...Nxe4 24.Nxe4 c5! 25.Nxc5 Qf3+, which seems good for Black but is not completely clear. They reckon White needs to find 22.Qa4!, when Black needs to find 22...b5! 23.Qxb5 Rxe4+ 24.Nxe4 Qxe4+, which they agree is dead-equal after 25.Kd2 Qd4+ 26.Kc2 Qe4+.
22...Qxh1 23.Rxh1 f5 24.Kf3 N4e5+ 25.Kg2 fxe4
Black regains his piece and will emerge two pawns up.
26.Nxe4 Nf7 27.Re1
With the threat of 28.Nf6+.
27...Re7 28.f3 Nd6 29.Bxd6 cxd6 30.Rd1 d5
Very pretty! Not only would it be unsafe to take the pawn (31.Rxd5 Nf4+), but the pawn itself is to play the biggest part in the final struggle.
31.Nc3 Rd7 32.Kf2 Ne7 33.Ke3 d4+ 34.Ke4
Not 34.Rxd4 Nf5+, but he could have held out longer with 34.Ke2. Now a fresh 'finesse' puts an end to the fight.
34...dxc3! 0-1
[White resigns] because of 35.Rxd7 c2 36.Rc7 Nc6.