Fundamentals (part 29)

Mark Lyell (2218) - Spanton (2039)
Hastings Challengers 2001-02

White to play and win

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51.h4!
The only winning move, eg 51.h3 can be met by 51...Kg6 (51...Ke6 also draws) 52.h4 Kf6, reaching the same position as after 51.h4! but with White instead of Black to move, which makes all the difference.
51...Ke6 52.Ke4 Kf6 53.Kd5 Ke7
Taking the opposition with 53...Kf7 actually loses quicker, according to the Nalimov endgame tablebase, eg 54.Ke5 Ke7 55.Kf5 Kf7 56.h5 Kg7 57.Ke6 etc.
54.Ke5 Kf7 55.Kf5 Kg7 56.Ke6 Kg6 57.Ke7 Kg7 58.h5 1-0

Fundamentals (part 17)

Spanton (147) - J Marley (153)
Sutton (London) Premier 1991

Black has just captured on d5 - who stands better?

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The position is dead-equal, according to the analysis engines Stockfish10 and Komodo10.
41.Kc3 Kc5 42.g4 g5?
42.f5 holds. The problem with the text is the white king will get access to the e4 square.
43.f5
This is probably good enough, but even stronger is 43.fxg5 fxg5 44.b4+! axb4+ 45.Kd3 Kd5 46.b3 h6 47.h3 when Black is in zugzwang. Note that if 42...f5 had been played, this idea does not work, eg 43.g5 Kd5 44.b4 axb4+ 45.Kd3 Kc5 - White's king cannot advance because the e4 square is covered. If in this line White plays 45.Kxb4 then 45...Ke4 leads to an equal queen-and-pawn ending.
43...Kb5  44.b4?
Winning seems to be 44.Kd4 Kb4 45.Kd5 Kxb3 46.Ke6 Kxb2 47.Kxf6 a4 48.Kxg5 - both players will queen but White will be a pawn up with what looks like sufficient shelter for his king as well as threats against Black's remaining pawn.
44...a4 45.Kd2 Kb4 46.h4!? h6
46...gxh4 also seems to draw.
47.hxg5 hxg5 48.Kc2
I offered  a draw.
48...Kc4

White to play and draw

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49.Kd2?
White holds with 49.Kb1 as 49...Kd4 50.Ka2 Ke3 51.Ka3 Kf3 52.Kxa4 Kxg4 is a draw, according to the Nalimov endgame tablebase.
The game finished:
49...Kd4 50.Kc2 Ke4 51.Kc3 Kf4 52.Kb4 Kxg4 53.Kxa4 Kxf5 54.b4 g4 55.b5 g3 56.b6 g2 57.b7 g1=R 0-1

Fundamentals (part 14)

Spanton (147) - D Ewart (148)
Highbury (London) Rapidplay 1990

White has just captured on c4 - who stands better?

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No prizes for guessing this ending arose from the Exchange Variation of the Spanish.
The analysis engines Stockfish10 and Komodo10 are not particularly impressed by the white position, but eventually agree White is slightly better. I suspect most humans would put White's advantage as higher than that - certainly White is the only player who can realistically hope for a win.
26...g5!?
Stockfish10 marginally prefers 26...a5. Komodo10 at one point sticks with 26...f5 for quite some time, but then switches to the text.
27.fxg5!?
The engines much prefer 27.g3, continuing 27...a5 28.b4 axb4 29.h4!? gxh4 30.gxh4 f5!? 31.e5 Kf7 32.Kxb4 with what they reckon is a large advantage for White, one line running 32...Ke6 33.Kc4 Ke7 34.Kc5 Ke6 when they continue to much prefer White, but do not come up with a continuation that makes progress.
27...fxg5 28.Kd4 c5+! 29.Ke3
The white king has to fall back as 29.Kxc5? is met by 29...Ke5 when White is close to being lost (the engines reckon Black is winning, but best play seems to lead to a queen-and-pawn ending in which Black is a pawn up, and is winning according to the engines, but the Nalimov endgame tablebase shows the position to be drawn).
29...h5!?
This seems to be OK, although at first the engines do not like it, but more natural is 29...Ke5.
30.g3
A better try seems to be the engines' 30.h4!?, eg 30...gxh4 31.Kf4 Kf6 32.e5+ Kg6 33.e6 Kf6 34.e7 Kxe7 35.Kg5 h3! 36.gxh3 Ke6 37.Kxh5, but 37...Kf5 looks to hold the draw.
30...c6?
Black seems to have a simple draw after 30...Ke5, and if, as in the game, 31.h4 then 31...g4 as Black has more reserve tempi and so can stop the white king penetrating.
31.h4 gxh4
Now 31...g4 is hopeless, but the text is no improvement.
32.gxh4 Ke5
At last, but too late - Black's reserve tempi will not save him as the white king can oscillate between f3 and e3 until the black king is forced to withdraw.
33.c3 b5 34.Kf3 b4 35.c4 a5 36.Ke3
The game finished:
36...Ke6 37.Kf4 Kf6 38.e5+ Ke6 39.Ke4 Ke7 40.Kf5 Kf7 41.e6+ Ke7 42.Ke5 Ke8 43.Kd6 Kd8 44.e7+ Ke8 45.Ke6 a4 46.bxa4 b3 47.Kd6 Kf7 48.Kd7 1-0

Fundamentals (part five)

Spanton (151) - Chris O'Bee (128)
Barbican (London) rapidplay 1989

Black has just captured on b5 - what should the result be?

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The position is drawn, but Black has to play accurately to get his half-share of the point, as can be seen from the fact Stockfish10 for quite some time reckons White is winning (Komodo10 quickly recognises the game should be a draw).
60.Kd3 Kc6 61.Ke4 Kd6
Too slow is 61...Kc4?, viz 62.Kxe5 Kd3 63.Kf5 Ke2 64.Kxg5 Kf2 65.Kxh4 Kxg2 66.Kg4 etc.
62.Kf5 Kd5 63.Kxg5

Black to play and draw

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63...e4?
Black draws by 63...Kd4 64.Kxh4 Ke3 65.Kg5 Kf2 66.h4 Kxg2 67.h5 Kxf3 68.h6 Kg2 69.h7 f3 70.h8=Q f2, reaching a position the Nalimov endgame tablebase confirms is drawn.
White could try the tricky 66.Kf5!? but the engines show the position is still drawn with correct play, ie 66...Kxg2 67.Ke4 (not 67.Kxe5? Kxf3 68.h4 Ke3 69.h5 f3 70.h6 f2 71.h7 f1=Q 72.h8=Q Qa1+) Kg3! (not 67...Kxh3 68.Kxe5 Kg3 69.Ke4 etc) 68.h4! (68.Kxe5 transposes to 67.Kxe5?) Kxh4 69.Kxe5 Kg5 70.Ke4 Kg6! 71.Kxf4 Kf6 - the final position is drawn because, with his pawn on f3, the white king needs to get to e5, f5 or g5 to force the pawn home (for a fuller explanation, see: https://beauchess.blogspot.com/2020/02/the-power-of-two-squares.html)
64.fxe4+ Kxe4 65.Kxh4 Ke3 66.Kg4 Kf2 67.Kxf4 1-0

The Power Of Two Minor Pieces

IT is well known that a bishop and knight are, other things being equal, superior to a rook and pawn, even though the value of both pairs is 6pts by the traditional counting method (Q-9, R-5, B-3, N-3, P-1).
But consider the following position, reached after a sequence such as 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Nc3 Bc5 5.Ng5 0-0

This position occurs 741 times in ChessBase's 2020 Mega database

In 141 games - almost a fifth of the total - White played either 6.Nxf7? or 6.Bxf7+?
Clearly the superiority of bishop and knight to rook and pawn, especially in the opening, is not so well-known as might be thought.
I believe the traditional counting method is largely to blame for this ignorance.
Database computer analysis by IM - now GM - Larry Kaufman shows the true average values are more like Q-9.75, R-5, B-3.25, N-3.25, P-1.
So giving up bishop (3.25) and knight (3.25) comes to 6.5pts.
But it is worse than this because the same computer analysis shows the bishop-pair to be worth 0.5pts, so in the example above White is giving up 7pts (B-3.25, N-3.25 and bishop-pair-0.5).
A rook is usually most powerful in endings where there are open files for it to operate on, whereas a knight is much more of a middlegame piece.
A search of my personal database reveals I have 30 times had an ending of bishop and knight versus rook, with various numbers of pawns on each side.
Some idea of the power of a rook in endgames can be gathered from the fact that in those 30 games, the player with bishop and knight won only 11 times, compared with 10 wins for the player with the rook (and nine draws).
Here is a recent correspondence example.

Black to make his 62nd move in Alexander Sherwood (2320) - Spanton (2260), 5th British Webserver team championship (division two) 2018

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Black has an extra pawn, and connected passers; White has a farside passed pawn.
62...Rb8
62...Rd8 is met by 63.Nc6, preventing ...d4.
63.Nb5 h4 64.Kf2 Kg5 65.Ke3 Re8+ 66.Kf2
White offered a draw.
66...Kf6 67.f4 g5 68.fxg5+ Kxg5 69.Nc7 Re5
69...Rd8?? 70.Ne6+.
70.Nb5 Kf4 71.a5 d4
There is no other way to make progress.
72.Nxd4 Rxa5 73.Bg6 Ra8 74.Bf7 Ke4

White to play and draw

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75.Bxc4!?
This shocks - assuming analysis engines can be shocked - Komodo10 and Stockfish10, whose evaluation changes from a small edge for Black to Black is winning.
But after …
75...Kxd4
… AS successfully claimed a draw, which indeed it is according to the Nalimov endgame tablebase (but I bet he would not have played 75.Bxc4!? over the board!).

Yesterday

HERE is my game from the 4NCL yesterday.
Spanton (1840/170) - Ryan Cheung (1681/149)
Division 4, Board 1, Wessex C v West Is Best 3
Spanish Exchange
1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Bxc6 dxc6 5.d4 exd4 6.Qxd4 Qxd4 7.Nxd4 Bd7 8.Be3 0-0-0 9.Nd2
If 9.Nc3, then 9...Bb4 is slightly annoying.
9...Ne7 10.f3
Normal is 10.0-0-0, but under the influence of my Lasker's Spanish Inquisition series, I wanted to keep my king  in the centre/kingside as Emanuel Lasker often did in 5.d4 lines of the Exchange Variation of the Ruy Lopez.
10...c5 11.N4b3 b6 12.a4?!
Castling long was still possible. The text creates a weakness as the white a pawn never manages to soften up Black's queenside, and anyway White is never likely to want to play axb6 as that would undouble Black's c pawns.
12...Nc6 13.Ke2 Be6 14.c3
Stockfish10 and Komodo10 prefer 14.Nc1 Nb4 15.Kd1, but give Black a large advantage.
14...f5 15.exf5 Bxf5 16.Ne4 h6 17.Rad1 Be7
The engines reckon Black should avoid allowing a rook-exchange, which lets White develop his king's rook, by playing, for example, 17...Bd7!?
18.Rxd8+ Rxd8 19.Rd1 Ne5?!
But now the engines reckon Black is much better after 19...Rxd1 20.Kxd1 Bd7.
20.Rxd8+ Kxd8 21.Nbd2 Be6
If 21...c4?, then 22.Bd4.
22.Bf4 Nc4 23.b3?
Correct is 23.Nxc4 Bxc4+ 24.Ke3, and if 24...Bb3, then 25.a5, when Stockfish10 reckons Black is slightly better, but Komodo10 rates the position as level.
23...Nxd2?
Black wins a pawn with 23...Na5 as 24.c4 fails to 24...Nxb3.
24.Nxd2 a5 25.Be5 g6 26.c4
White has stabilised the queenside and still has a kingside pawn-majority, but the bishop-pair is so powerful the engines reckon the position is dead-level.
26...Bd6!? 27.Bf6+!?
The engines reckon that after 27.Bxd6 cxd6 White may be slightly better, but I felt there were zero winning chances.
27...Kd7 28.g3 Bf5 29.Ne4 Ke6 30.Bc3 h5 31.Ke3 Be5 32.Bxe5 Kxe5 33.f4+ Ke6 34.Nd2 Bc2 35.h3 Kf5 36.Ke2??
36.Kf3 holds the balance.
36...g5?
Missing a win by 36...h4, eg 37.Kf2 hxg3+ 38.Kxg3 Bd1, when White is in zugzwang after 39.h4 c6, or 37.gxh4 Kxf4 38.Kf2 c6, and again White is in zugzwang.
37.fxg5 Kxg5 38.Kf3 Bf5
Black has to be careful after this. It was simpler to maintain pressure on the white queenside by 38...Kf5, as 39.g4+ hxg4+ 40.hxg4+ Ke5 seems strong for Black.
39.Ne4+ Kg6?
39...Kh6 40.g4 hxg4+ 41.hxg4 Bg6 42.Kf4 Kg7 43.Ke5 Kf8 holds.
40.g4 Bd7
40...hxg4+ 41.hxg4 Bd7 42.Kf4 also looks problematic for Black, as does 40...Be6 41.Kf4.
41.gxh5+ Kh6
Not 41...Kxh5?? 42.Nf6+.
42.h4 Bh3 43.Ng3 Bd7 44.Kf4 c6
There does not seem to be any defence.
45.Ke5 Bg4 46.Kd6 Bf3
Or 46...Bd1 47.Kxc6 Bxb3 48.Kxb6 Bxa4 49.Kxa5 etc.
47.Kc7 b5!?
This gives White chances to go wrong.
48.cxb5 cxb5 49.axb5 c4 50.bxc4 a4 51.Nf5+ Kxh5 52.Nd4 Bd1 53.b6?
Much simpler is 53.Nc6 a3 54.Nb4 as Black cannot stop one of White's queenside pawns promoting.
53...a3 54.b7 a2 55.b8=Q a1=Q 56.Qh8+ Kg4 57.Qg7+?!
Best, according to the engines, is 57.c5.
57...Kh3
Not 57...Kxh4?? 58.Nf5+ Kh5 59.Qxa1.
58.Qd7+ Bg4 59.Qd5 Kxh4
Now White only has a one-pawn advantage, which means Black draws if he can sac his bishop for the pawn.
60.Nb5 Qg7+ 61.Kb6 Qf6+ 62.Nd6 Qb2+ 63.Kc5 Qa3+ 64.Kd4 Qb2+ 65.Kc5 Qa3+ 66.Kb6 Bf3 67.Qd4+ Kh3 68.Nb5 Qa8 69.Qd7+ Kg2 70.Qc7 Qf8 71.c5
After a lot of manoeuvring, the pawn advances, but Black still has decent drawing chances. Stockfish10 reckons the position is equal, but Komodo10, which I think sometimes overvalues material differences in endings, reckons White has the upper hand.
71...Qf6+ 72.Qd6

Should Black exchange queens?

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72...Qg5?
72...Qxd6+ 73.cxd6 Bg4 74.Kc7 Kf3 75.Kc6 Ke4 76.Nc3+ Ke5 is a draw, according to Stockfish10, but Komodo10 still believes White has the upper hand. The Nalimov endgame tablebase shows exchanging queens does indeed draw.
73.Nd4
The engines agree White is much better.
73...Bg4?!
The bishop should surely stay on the long light-square diagonal, ready to capture if the pawn advances.
74.c6 Qc1 75.Qd5+ Kh3 76.c7 Qb2+ 77.Nb5 Qf2+ 78.Qd4?
78.Nd4 is better.
78...Qf5?
Stockfish10 reckons 78...Qxd4+ 79.Nxd4 Kg3 is a draw; Komodo10 has White winning. Again Stockfish10 is correct, according to Nalimov.
79.Nd6 Qb1+ 80.Ka7 Qa2+ 81.Kb8 Qb3+ 82.Nb7 Qg3 83.Qh8+ Kg2 84.Qb2+ Kg1 85.Qb6+ Kg2 86.Nd6 Qh3 87.Qb2+ Kg1 88.Ne4 Qf3 89.Qd4+ Kg2 90.Qd2+ Kg1 65mins less 91.Qb4 Qf4 92.Qb1+ Kg2 93.Qb2+ Kf3 94.Nf6 Bf5 95.Qc3+ Kf2 96.Nd5 Qf3 97.Qd2+ Kg3 98.Qe1+ Kg4?
The engines have had White winning since Black's 78th move, but I was not finding it easy. However now White can exchange minor pieces and so eliminate Black's ...BxP drawing resource.
99.Ne3+ Kf4 100.Nxf5 Qb3+ 101.Kc8 Kxf5 102.Qe8 Qb6 103.Qe7 Kf4 104.Kd7 Qb5+ 105.Kd8 Qd5+ 106.Ke8 Qa8+ 107.Kf7 Qd5+ 108.Kg6 Qg2+ 109.Kh7 Qh3+ 110.Kg8 Qg4+ 111.Kf8 Qc8+ 112.Kf7 Kf3
The checks have effectively run out as 112...Qf5+? loses trivially to 113.Qf6.
113.Qd8 Qb7 114.Qd7 Qb3+ 115.Kf8 Qb4+ 116.Qe7 Qb7 117.Kg7 Kg3 118.Qe5+ Kf3 119.Kg6 Kg2 120.Kg5 Qc8 121.Qe4+ Kg3 122.Qf4+ Kh3 123.Qh4+ 1-0

My Best Ever Tournament (part five)

Spanton (2096) - Marco Sbarra (2269)
Lausanne 1999 Round 5
Sicilian Maroczy Bind/English Symmetrical
1.e4 c5 2.c4!?
The idea is to proceed, depending on Black's response, with a Maroczy Bind or a Botvinnik formation in the English.
2...Nc6 3.Ne2 Nf6 4.Nbc3 e6 5.d4 cxd4 6.Nxd4 Nxd4?!
Black does not usually bring White's queen to d4 in the Sicilian if its position cannot be challenged with tempo. Normal is 6...Bb4.
7.Qxd4 d6 8.Bg5 Be7 9.0-0-0!?
Emphasising development, but it is very unusual for White to castle long in a Maroczy.
9...Bd7 10.f4 Qb6 11.Bxf6 gxf6?!
Probably better is 11...Bxf6, and if 12.Qxd6, then 12...Bc6 with very promising compensation for a pawn.
12.Qxb6 axb6 13.Kb1 Rg8 14.Rd2 Bc6 15.Bd3 0-0-0 16.Rhd1 Rg7
MS said in the postmortem he should have dispensed with this, at least in the short-term, and played 14...h5. The analysis engines Stockfish10 and Komodo10 agree.
17.Bc2!?
The engines strongly dislike this, preferring 15.g3.
17...h5 18.b4 f5 19.b5 Bxe4 20.Bxe4
Possibly better was 20.Nxe4.
20...fxe4 21.Nxe4 Kc7 22.Kc2
I spent a long time trying to make 22.f5 work but, after 22...Rg4 could not see 23.Re2. Having said that, there is nothing special about 22.f5 anyway.
22...f5 23.Nc3 Bf6 24.Re1 Re7 25.Rde2 Bxc3 26.Kxc3 Kd7 27.Kd4
I offered a draw.
27...Rg8

White to make his 28th move

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28.a4?!
I was oblivious to the danger posed to the white position by the undefended f pawn being on the same rank as the king.
28...Ree8
Black can start to pressurise with 28...Rg4 29.Ke3 e5, when then position is, if nothing else, easier for Black to play.
29.Ra1?!
Prophylaxis on the a file, but prophylaxis over f4 was more important, calling for a move such as 29.g3.
29...Ra8?!
This accomplishes nothing; again, ...Rg4 was better.
30.Ra3?!
Correct was 30.Rae1, and if 30...Rge8, then 31.Ra1.
30...Rg4 31.g3?!
Almost certainly a better defence was provided by 31.Ke3.
31...e5+ 32.Ke3?
Other king retreats were better as now Black's next comes with check.
32...exf4+ 33.Kf3?
A fingerslip - I meant to play 33.gxf4.
33...fxg3 34.hxg3?
Yet another mistake. Better is first 34.Rae3, threatening mate-in-three.
34...Rxc4?
Stronger is 34...Rag8, but by now Black's advantage is so large that the text is probably good enough.
35.Rae3 Re4 36.Rxe4 fxe4+ 37.Rxe4 Rf8 38.Kg2?!
Centralisation with 38.Ke3 is almost certainly better.
38...Rf5 39.Kh3?
Further decentralisation!
39...d5 40.Rd4 Kd6 41.g4 hxg4+ 42.Kxg4 Rf7 43.Rd1 Kc5 44.Rc1+ Kb4 45.Rd1 Rd7 46.Rd4+
46.Kf5 Kxa4 47.Ke6 Rd8 48.Ke7 Rc8 49.Rxd5 Rc5 50.Rd7 Kxb5 also wins for Black, as the Nalimov endgame tablebase confirms.
46...Kc3 47.Rd1 d4 48.Kf3 d3 49.Ke3 d2 0-1

Ridiculous Blunder

PLAYED  a Scot in this morning's ninth and final round of the Mariánské Lázně 50+ seniors.

White to play and draw in Spanton (1854) - Ian Aird (1857)

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49.Rd4??
The double-question mark is not so much for playing a losing move - the position is not simple - but because I knew how to work out whether the pawn-ending is drawn or lost, but I played the text anyway.
The only drawing move is 49.Re4+!!, and after 49...Kf5, 50.Re1!! Stockfish10 and Komodo10 reckon Black's best try is 50...Rf2 51.Kd4!! Kf4 52.Re4+! Kg3 53.Re3+! Kg4 54.Re1!! f5 55.Ke3! Rg2 56.Rf1! Rg3+ 57.Ke2! So far all of White's moves have been only-moves, and I have tried to punctuate them in line with the John Nunn endgame convention.*
From now on it gets easier for White, for example 57...f4 allows five drawing moves, all with the rook, including 58.Rh1, while 57...Rh3!?, which is probably Black's best shot, allows two, 58.Rg1+ and 58.Rf2 (all analysis courtesy of the Nalimov endgame tablebase).
The game finished:
49...Rxd4+! (still using the Nunn convention) 50.Kxd4 Kf5 (for some reason I had only considered 50...f5??) 51.Ke3 Kg4 52.Ke2 Kg3 53.Ke3 f5 0-1
My final score of +4=2-3 saw me lose 11.2 Fide elo.

*From Wikipedia:
In his 1992 book Secrets Of Rook Endings and other books in the series (Secrets Of Minor-Piece Endings and Secrets Of Pawnless Endings), John Nunn uses … symbols in a more specific way in the context of endgames where the optimal line of play can be determined with certainty:
 ! - The only move which maintains the current evaluation of the position: if the position is theoretically drawn, this is the only move which does not lose; if the position is theoretically won, this is the only move which secures the win. An "!" is used no matter how trivial the move in question; the only exception is if it is the only legal move.

 !! - A particularly difficult-to-find "!" move.

 ? - A move which negatively affects the evaluation of the position: if the position had been drawn before the move, it is now lost; if won before the move, it is now drawn or lost.

 ?? - An obviously bad "?" move.

 !? - A move which makes the opponent's task harder or one's own task easier; for example, in a theoretically lost position, a move which forces the opponent to find several "!" moves in order to win.

 ?! - A move which makes the opponent's task easier or one's own task harder; for example, in a theoretically won position, a move which requires several subsequent "!" moves in order to win (Nunn 1999).

This convention has been used in some later works, such as Fundamental Chess Endings and Secrets Of Pawn Endings by Karsten Müller and Frank Lamprecht, but it can be safely assumed the convention is not being used unless there is a specific note otherwise. The Nunn convention cannot be used to annotate full games because the exact evaluation of a position is generally impractical to compute.

Most Extraordinary Finish To A Chess Game EVER!

THAT is a big claim, but I have certainly never experienced anything like the finish of my game today in round one of the Mariánské Lázně seniors (50+).

Black to make his 45th move in Spanton (1854) - Imrich Tamas (1520)

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45...Rxf5!?
A good practical choice. The pawn-ending is lost, but there are chances for White to go wrong, more so than if Black moves the rook away and gives up his h pawn, leaving him three pawns down.
46.Kxf5 a3 47.bxa3
Not 47.b3+?? Kc3 48.h3 (worse is 48.Kg5? as White does not even get to queen after 48...Kb2 49.Kxh5 Kxa2 50.g4 Kb2 51.g5 a2 52.g6 a1=Q etc) Kb2 49.g4 Kxa2 50.g5 (50.gxh5?? Kb1 etc) Kb2 51.g6 a2 52.g7 a1=Q 53.g8=Q Qf1+, when Black picks up the h3 pawn and wins thanks to having the only passed pawn and a relatively safe king. Note that 48.Ke4 loses to 48...Kb2 etc.
47...bxa3

White to play and win

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48.g4??
This is Komodo10's choice, until it switches to 48.h4?? which, like the text, also throws away the win. Correct is 48.Kg5 (or 48.Kg6) Kc3 49.Kxh5 Kb2 (49...Kxc2? is hopeless) 50.c4 Kxa2 51.c5 Kb1 52.c6 a2 53.c7 a1=Q 54.c8=Q, when the Nalimov endgame tablebase confirms the queen-and-pawn ending is won for White.
48...hxg4 49.Kxg4 Kc3 50.h4 Kxc2
Not 50.Kb2?? as the c pawn will win for White after both the h and a pawns promote.
51.h5 Kb2 52.h6 Kxa2 53.h7 Kb1 54.h8=Q a2 55.Qh1+ Kb2 56.Qb7+

Now comes the extraordinary part - Black to make his 56th move

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1-0
IT resigned, and took some convincing the position is drawn. Any king move not to the third rank, which allows 57.Qg7(+), draws. Simplest is 56...Ka1, setting up stalemate. A similar stalemate motif applies with a bishop's pawn against queen.

Marathon Battle

FACED a junior on top board for Wessex C against MK Phoenix 2 in division four of the 4NCL yesterday at the Holiday Inn, Maidenhead.
Toby Cox (1690/164) - Spanton (1854/168)
Sicilian Morra Gambit Declined
1.e4 c5 2.d4 cxd4 3.c3 g6 4.Nf3
The main line goes 4.cxd4 d5, when White usually chooses between 5.exd5 and 5.e5.
4...Bg7 5.Bc4 e6 6.Qe2!?
A very rare move. The idea, presumably, is to prevent ...d5, but it does not achieve this.
6...Ne7 7.0-0 Nbc6 8.Bg5?!
This too does not prevent ...d5, and meanwhile the bishop is a target.
8...h6
Already possible is ...d5, but putting the question to the bishop first seems sensible.
9.Bf4
On 9.Bh4, Stockfish10 and Komodo10 like 9...g5 10.Bg3 d5.
9...d5 10.exd5 Nxd5
Maybe even stronger is 10...exd5, but the text is good enough for a pleasant advantage.
11.Be5?!
Stockfish10 and Komodo10 give 11.Bxd5 Qxd5 12.Rd1, but prefer Black.
11...Nxe5 12.Nxe5 0-0
I rejected 12...Nf4 because of 13.Qe4, but I should have looked further as Black has 13...Nxg2! (13...Qh4!? may also be good), and if 14.Bb5+, then 14...Kf8. Also probably good is 12...dxc3!? 13.Bb5+ Kf8 14.Nxc3, although giving up castling rights for the sake of a pawn is double-edged.
13.cxd4 Nb6 14.Nf3
14.Rd1 Nxc4 15.Nxc4 (15.Qxc4?? Bxe5) b6 is good for Black, and if 16.Qe4, then simply 16...Rb8 and ...Bb7.
14...Nxc4 15.Qxc4
Black has the bishop-pair on a fairly open board, and White has a weak d pawn. Stockfish10 reckons Black is winning, but Komodo10's verdict of 'only' having the upper hand seems more realistic.
15...Bd7 16.Nc3 Rc8 17.Qe2 Bc6 18.Rfd1 Qa5
I rejected the engines' choice 18...Qb6 because of 19.d5, but 19...exd5 20.Nxd5 Bxd5 21.Rxd5 Rfe8 is strong for Black.
19.Rd3?!
Lining up rook and queen on the same diagonal is often unwise when the opponent has the bishop-pair.
19...b5 20.Ne4
Stockfish10's choice. Komodo10 prefers 20.d5 b4 21.dxc6 bxc3 22.bxc3 Rxc6, but with a clear advantage for Black.
20...Bxe4
This is fine for a continued advantage, but 20...b4 was consistent and good. Also natural was 20...Rfd8.
21.Qxe4 Rc2 22.Ra3 Qc7 23.Rxa7 Rc1+ 24.Rxc1 Qxc1+ 25.Qe1 Qxb2
The engines prefer 25...Rc8 on the basis that the b2 pawn cannot be saved as 26.b3 Bxd4 is hopeless for White.
26.h3 Rc8?
Forgetting that Black also has king-safety issues. Simple and good was 26...Bxd4.
27.Qe4 Qc1+ 28.Kh2 Qc6 29.Qf4 f6?
29...f5 holds as 30.Ne5 can be met by 30...Qb6 with ...g5 to follow.

How does White get a large advantage?

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30.Ne5! Qe8
30...fxe5?? 31.Qf7+ Kh8 32.Qxg7#.
31.Ng4 Qf8!?
Probably objectively better was 31...Ra8 eg 32.Nxf6+ Bxf6 33.Rxa8 Qxa8 34.Qxf6 Qe8, but White is winning.
32.Qe4 Qe8 33.Qb7 Qf8 34.Nxh6+!
The engines prefer this to 34.Nxf6+, which is completely winning for White after 34...Qxf6?35.Qxc8+ Kh7 36.Qc7, but 34...Kh8 keeps the game going.
34...Kh8 35.Ng4
35.Qd7 leaves Black almost in zugzwang. The engines also point out 35.Nf7+ Kg8 36.Qxb5.
35...Rd8 36.g3 b4
36...Rxd4 is met by 37.Qxb5.
37.Qb6
The engines reckon White can give up the d pawn by 37.Ne3!? Rxd4, when Stockfish10 continues 38.h4 f5 39.Ng2 e5 40.h5! gxh5 41.Nh4 with numerous threats to the drafty black king.
7...Qd6 38.Qb7 Qf8 39.Qb6?
This was the last chance for 39.Ne3, or some other move, as now Black gets his pawn back with an equal position.
39...Qd6 40.Qxd6 Rxd6 41.Rb7 Rxd4 42.Kg2 f5 43.Ne3 Re4 44.Kf3 Kg8 45.Ke2 Bc3 46.Rd7 Kf8 47.Kf3 Ke8 48.Rd1 Ke7
Rook and bishop usually work better together than rook and knight, but here that is balanced by the vulnerability of the b pawn.
49.Ke2 Re5 50.Rc1 Ra5 51.Rc2 g5 52.Nd1 Be5 53.Ne3 Ra8 54.Kd3 Bc3 55.Re2 Kf6 56.Kc4 Rd8
56...Rc8+ 57.Kb3 Rh8 58.Nc2 Rxh3 59.Nxb4 Be5 holds the balance more easily.
57.Nc2 Rh8?
57...Rc8+ 58.Kb3 Be5 59.Nxb4 Rc3+ 60.Ka4 f4 61.gxf4 gxf4 62.h4 is equal, according to the engines, but looks easier for White to play.
58.Nxb4 Bxb4 59.Kxb4 Rxh3?
59...Rb8+ 60.Kc3 Ra8 holds, according to the engines.
60.a4
White gets his rook behind his passed pawn, giving him excellent winning chances.
60...Rh1 61.Ra2 Rb1+ 62.Kc3 Ke5 63.a5 Kd5 64.a6 Rb8 65.a7 Ra8 66.Ra5+?
Wrong technique. The rook is ideally placed defending White's kingside while supporting his passer. Correct therefore was 66.Kb4, eg 66...Kc6, and now 67.Ra6+ as 67...Kd5, trying to attack the kingside, is by now hopeless.

How should Black respond to White's mistake?

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66...Kd6??
Poor. Black had to try 66...Ke4, when 67.Ra2 gives Black very good drawing chances with 67...e5 or 67...g4.
The engines give 67.f4 g4 (67...gxf4 68.Ra4+ Kf3 69.gxf4 and the white rook is again ideally placed, defending the kingside while supporting White's passer.) 68.Kc4 e5 (68...Kf3 69.Ra3+) 69.fxe5 (69.Rxe5+? Kf3=) f4 70.e6 fxg3 71.e7 g2 72.Ra1 Kf3 73.Kd5 Kf2 74.Kc6 g1Q 75.Rxg1 Kxg1 76.Kb7 Re8 77.a8Q Rxe7+. The engines reckon White wins with 78.Kc6, but the Nalimov endgame tablebase shows the position is drawn.
The game finished:
67.Kd4 g4 68.Ra6+ Ke7 69.Ke5 Kf7 70.Kd6 Kf6 71.Kd7 f4 72.gxf4 Kf5 73.Ra4 e5 74.fxe5 Kxe5 75.Kc7 1-0
MK Phoenix 2 won the match 4.5-1.5.

When It Paid To Trade Down To A Pawn Ending

I MENTIONED in my post on Sunday at the end of Hastings (https://beauchess.blogspot.com/2020/01/hastings-concluded.html) that the materially-weaker side in an endgame should nearly always avoid exchanging into a pawn-ending.
I added that I could only recall one instance off the top of my head when I successfully traded down to secure a draw, although that was against an international master.

A pair of rooks has just been exchanged on e2 in Spanton (2096) - Viesturs Meijers (2418), Lausanne 1999

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33...Rb6
The analysis engines Komodo10 and Stockfish10 reckon Black should start with 33...g5!?, but I do not see how this helps Black after the obvious 34.hxg5 hxg5 (but read on to see why they are probably right).
Latvian IM - now GM - Meijers tries a different approach.
In general it can be said that if the black rook were defending the extra pawn from somewhere on the a file, this position would be drawn (at least if I am reading Reuben Fine correctly in Basic Chess Endings).
However, James Howell says in Essential Chess Endings that the situation can be very different if the extra pawn is being defended from the side. "The key to success," he writes, "is to arrange his pieces so that his rook is not only defending the passed pawn but also the base of his pawn-chain on the other wing. [White] might try to create counterplay by advancing his king and pawns but in principle there shouldn't be anything stopping the [black] king coming over to shepherd the pawn home."
That would suggest Black should start here with 33...Kf8. But 34.Ra8+ Ke7 35.Ra7+ Kd8 is met by 36.g5, forcing the black rook to give up defending either f7 or a6. Now I understand why the engines recommend 33...g5.
34.h5 Kf8
In my original notes to the game, I suggested Black should try 34...g6. I suspect my idea was that 35.hxg6 fxg6 would give Black hope of creating a second passed pawn. However, the engines reckon the position is dead drawn, presumably because the black king is cut off on the back rank. They reckon Black gets a slight edge by recapturing with 35...Rxg6, although it is hard to see this position being seriously dangerous for White.
35.Kd3 g6 36.hxg6 fxg6
The engines still prefer ...Rxg6, but give Black little chance of converting.
37.Rh7
Ruling out any possibility of the black h pawn becoming passed.
37...g5 38.Kc4 a5 39.Ra7 Rf6 40.Rxa5 Rxf3
My annotation to this move 20 years ago reads: "Fritz5 now has Black at plus over minus, verging on winning, and yet the position looks very drawish." I was right, according to Komodo10 and Stockfish10.
41.Ra6 Rf4+ 42.Kd3 Kg7
White has a much easier draw after 42..Rxg4 43.Rxh6.
43.Ra7+ Kg6 44.Ra6+ Rf6 45.Rxf6+!
VM's body language suggested he was very surprised by this move - he presumably took it as granted White should keep rooks on.
In my original notes I point out that 45.Ra4? h5 46.Ke3 hxg4 47.Rxg4 Kh5 46.Ra4 g4 "is a win according to Fine," and this is confirmed by Nalimov (at least after 46...hxg4 or 45.gxh5+). But it is quite possible other rook moves, eg 45.Ra8, also draw.
45...Kxf6

What are the keys to White's defence?

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The first point is that if the black king can ever get to e5, the white king must be able to oppose it by occupying e3. The second point is that if Black organises the sequence ...h5, gxh5+ Kxh5, Black only wins if his king can get to f3, g3 or h3.
46.Ke4
From the above, it can be seen 46.Ke2 also draws, but 46.Ke3?? is a gross blunder as the black king gets to e5 with White to move.
46...Kg6 47.Kf3 Kf7
Or 47...h5 48.gxh5+ Kxh5 49.Kg3=.
48.Ke3 Ke7 49.Ke4 Ke6 50.Kd4
The only move to draw. Note that the sequence 50.Kd3?? Ke5?? 51.Ke3 also draws, but in this case Black wins with 50...Kd5.
50...Kf7 51.Ke3 Kg7 52.Ke4 Kf6 53.Kf3
Another only move. Note that this time Kd3?? loses to 53...Kg6 54.Ke3 h5 55.gxh5+ Kxh5 56.Kf3 Kh4 57.Kg2 Kg4 as the black king gets to h3 or f3.
The similar blunder 56.Kd4?? (the position was reached with three more moves on the scoresheets) was played in Murat Eren Aytekin (2063) - Georgi Petrov (2207), EU Amateur U2300 Championship 2007. The game finished 56...Kg6 57.Ke4 h5 58.gxh5+ Kxh5 59.Kf3 Kh4 60.Kg2 Kg4 61.Kh2 Kf3 62.Kh1 Kg3 63.Kg1 g4 0-1.
53...Ke5
This position, but with Black to move, was reached in Friedrich Dicks - Ludger Lautenschütz, Recklinghausen 2002, and Omran Al Hosani (2101) - R Ashwath (2250), Sharjah Masters 2018. In both games, Black won quickly by outflanking White with ...Kd4.
54.Ke3 Kd5
In Vladimir Anchikov - Lazar Ivic (1648), World Schools U9 2013, Black tried 52 ...Kf6 (the position was reached with two fewer moves having been played), when White blundered with 53.Kd4??, either forgetting, or being unaware, that Black could win down the h file. The game concluded 53...Kg6 54.Ke3 h5 55.gxh5+ Kxh5 56.Kf2 Kh4 57.Kf1 Kh3 58.Kf2 g4 59.Kg1 Kg3 60.Kh1 Kf2 61.Kh2 g3+ 62.Kh1 g2+ 63.Kh2 g1=Q+ 64.Kh3 Qg3#.
55.Kd3 Ke5 ½–½

Morphy v The Petrov

PAUL Morphy always played 1.e4 as White, and 79.5% of his games continued 1...e5.
Nevertheless Morphy only faced the Petrov six times, despite it being a popular defence in the mid-19th century.
Perhaps this had something to do with Morphy being recognised as a genius of Open games, and there may have been a feeling that the Petrov allowed a very-open Open game.
Although Morphy only faced the Petrov seven times, he tried three different systems against it.
He seems to have respected the Petrov - he certainly rated the defence enough to try it three times in his celebrated match against Johann Löwenthal.
Morphy first faced the Petrov in a 'casual'* game in 1850 against the same Löwenthal.
Morphy - Löwenthal
Petrov Defence Cozio Attack
1.e4 e5 2.Nf3 Nf6 3.Nxe5 d6 4.Nf3 Nxe4 5.Qe2!?

Position after 5.Qe2!?

Wikipedia attributes this move to Lasker. But while it became a favourite of his - and of Capablanca - it is normally credited to the 18th-century Italian Carlo Cozio. This game is the first in which it appears in ChessBase's 2019 Mega database. It probably appealed to Morphy because White aims for a small lead in development in a symmetrical pawn-structure, and therefore is reminiscent of his play against the French.
5...Qe7 6.d3 Nf6 7.Nc3!?
Normal is 7.Bg5, but Carlsen, Ivanchuk, Nakamura and So have experimented with the text. It is also the preference of the engines Stockfish10 and Komodo10.
7...Be6 8.Bg5 h6 9.Bxf6!?
Giving up the bishop-pair in the interest of speedy development. Capablanca also played this way in a win over Marshall at St Petersburg 1914.
9...Qxf6 10.d4
Löwenthal notes in his Morphy's Games Of Chess: "10.Nd5 does not yield any advantage as Black can safely reply with 10...Qxb2."
10...c6?!
Marshall played 10...Be7?! against Capablanca, only to be hit with 11.Qb5+. Marshall was an attacking player, and probably sacrificed his b pawn deliberately (he played the same move 11 years later against Mieses), but the idea is not liked by the engines.
Those same engines reckon Black's best is 10...Qe7, in which case White has a slight lead in development, but Black has the long-term advantage of the bishop-pair.

White to make his 11th move

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11.0-0-0?!
Morphy seems to have missed a trick here. 11.d5, as pointed out by Löwenthal, is strong. After the forced 11...cxd5, Löwenthal gave 12.Nxd4, but that allows unclear complications with 12...Qxb2. Better, as given by the engines, is 12.0-0-0, when White will recover his d pawn while leaving Black with a weakness at d6 and a lag in development.
11...d5
 "In order to prevent the advance of the [white] d pawn" - Löwenthal.
12.Ne5 Bb4 13.Nxd5?
A rare miscalculation by Morphy. An anonymous annotator in ChessBase suggests 13.Qe3.
13...Bxd5 14.Ng6+
This is better than 14.Nxc6+ Be7, eg 15.Nxe7 Qxe7 16.Qh5 Qg5+.
14...Qe6?
White is better after this. What both players missed is 14...Kd7! After 15.Nxh8 Na6 19.Nxf7 Qxf7, White has rook and two pawns for bishop and knight. This may be OK materially, but Black has open lines for his bishop-pair, and White has problems untangling his kingside. Meanwhile, the black king is safe on d7 as White has no pieces that can get at it.
15.Nxh8 Qxe2
Best, according to the engines, but the whole sequence helps White activate his kingside.
16.Bxe2 Kf8 17.a3
ChessBase gives "17.c4! Be6 18.d5 cxd5 19.Bf3 Kg8 20.Bxd5 Bxd5 21.Rxd5," when ChessBase's 21...Kh8? loses to 22.Rd8+ etc. However, Black can improve with 21...Be7, when White will again emerge with rook and two pawns for bishop and knight, but this time Black will not have the bishop-pair, and White will have no problems with kingside development. The engines prefer White.
17...Bd6 18.Bd3
Better is ChessBase's 18.Bh5! as White subsequently gets rid of Black's bishop-pair with a double-capture on f7.
18...Kg8?!
Löwenthal: "18...Bxg2, although it looks hazardous, might have been played with advantage." Certainly, 19.Rhg1 is nothing to be worried about. But Löwenthal may have feared 19.Bc4 Bd5 20.Bxd5 cxd5 21.Rd3, but the engines reckon Black is much better after 21...Nd7.
19.Nxf7 Kxf7 20.f3 b5 21.Be4 Nd7 22.Rde1 Nf6 23.Re2 Re8?
A positional error that I suspect many club players today would know to avoid. The point is that, as a general rule, when you have one rook and the opponent has two, it is a mistake to exchange a pair as the opponent's two rooks have a degree of redundancy.
24.Bxd5+ cxd5 25.Rxe8 Nxe8 26.g3 g5 27.Kg2 Ng7 28.Ra1 a5 29.Kd3 Ke6 30.a4 b4 31.c4!
Löwenthal: "An excellent move."
31...Bc7
Black faced a tricky decision. Neither Stockfish10's 31...dxc4+ 32.Kxc4, nor Komodo10's 31...bxc3 32.Re1+ Kd7 33.bxc3, seems satisfactory for Black.
32.Re1+ Kd6 33.Re5 dxc4+ 34.Kxc4 Ne6 35.Rb5 Nf8 36.Rd5+ Ke6 37.Rc5+ Kd6 38.d5 Kd7 39.Rc6 Bd6 40.Ra6 Ng6 41.Rxa5
Morphy's skilful rook manoeuvres have netted him a second pawn, and an overwhelming advantage.
41...Ne5+ 42.Kb5 b3!?
Hoping to make this pawn passed and thus create counterplay. 42...Nxf3 is met by 43.Ra7+, eg 43...Kc8 44.a5 Nd4+ 45.Kb6, and the a pawn will cost Black a piece.
43.Ra7+ Kd8 44.f4 gxf4 45.gxf4 Nd3 46.Kxc4 Nxf4 47.Rh7 Be5 48.Rxh6 Bxb2 49.Kxb3 Bg7 50.Rh7 Be5 51.a5 Nxd5!?
ChessBase gives this a question-mark, but Black is lost in any case.
52.Rxh5 Bxh2 53.Rxd5 Kc8 54.Rb5 Kc7 55.Kc4 Kc6 56.Rh5 Bg1 57.Rh6+?
The engines reckon White is still winning after this, but the position now seems to be drawn. Correct, as pointed out in ChessBase, is 57.Rh7 followed by a6 etc.
57...Kc7?
In Morphy's Games Of Chess, there comes the note: "After a few moves the game was declared drawn."
But Black is losing here. He should have played 57...Kb7, which draws, as a check with the Nalimov endgame tablebase shows.
In ChessBase the game continues:
58.Kb5?
A mistake. As ChessBase points out, White wins with 58.Rh1 Be3 59.Rb1 Kc6 60.a6 Bb6 61.Rb5 Ba7 62.Rb7 Bb6 63.Rf7 followed by a7 etc. If in this line Black tries 61...Kc7, then 62.Kd5 leads to similar play.
58...Kb8 ½–½
ChessBase claims White is winning, as indeed do the engines. But the Nalimov endgame tablebase shows the position to be drawn.
*As I pointed out in my series on Morphy v The French, most games in Morphy's times were 'casual' - tournaments were rare and matches not much less so.

More Double Trouble

FOR the second time in this year's Olomouc seniors, I was double-upfloated as Black against a titled player.
In round five it was against the top seed; today in round eight it was against the second seed.
Sergej Shilov (FM2129) - Spanton (1881)
Chigorin
1.d4 d5 2.Nf3 Nc6 3.c4 Bg4 4.cxd5 Bxf3 5.gxf3 Qxd5 6.e3 e5 7.Nc3 Bb4 8.Bd2 Bxc3 9.bxc3 Nf6!?
This has been recommended by Chigorin-guru Morozevich, although it is the first time I have played it. More common in ChessBase's 2019 Mega database are 9....Qd6 and 9...exd4.
10.c4 Qd6 11.d5 Nb8
Nigel Short is among those who have played the more popular 11...Ne7.
12.Rb1 b6 13.Rg1!?
This may be a new move; it is the choice of the analysis engine Stockfish10, although Komodo9 narrowly gives the nod to 13.Bb4.
13...g6 14.Bb4 c5 15.dxc6!?
Opening lines for the bishops, but the engines prefer to keep the protected passed pawn with 15.Bc3.
15...Qxd1+ 16.Rxd1 Nxc6 17.Ba3 Rd8 18.Bd3

Black faces a tricky task as White's bishops and better development more than outweigh his inferior pawn-structure

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18...e4!?
I rejected the engines' 18...Nd7 because of 19.Bd5, when Stockfish10 gives 19...Na5 20.Bd5 Rc8. White then has a pleasant choice between winning a pawn with 21.Bxf7+ Kxf7 22.Rxd7+, and Stockfish10's preferred 21.Ke2!? Nxc4 22.Rc1 b5 23.Rgd1 a5 24.Bxc4 Rxc4 25.Rxc4 bxc4 26.Rd6, with plenty of play for being a pawn down (Black still has problems getting his king's rook into play, and the black queenside pawns are very weak).
19.fxe4
The engines prefer this to the alternative capture 19.Bxe4, but even better seems to be a move I did not consider, 19.Bc2! The point is that after 19...Rxd1+ 20.Kxd1, Black cannot play 20...exf3?? because of 21.Ba4 Kd7 22.Bb2. So in this line Black is more-or-less obliged to play 20...Kd8, when 21.fxe4 leaves White a pawn up. Black could instead try 19...Ne5!?, but then 20.Ba4 Nfd7 21.Rd5! is very strong for White, eg 21...Nxf3+ 22.Kd1 Nxg1? 23.Re5#. Black has alternatives in this last line, but none seems good.
19...Ne5 20.Ke2
Black is at least equal after 20.Be2? Rxd1+ followed by ...Nxe4.
20...Nxd3 21.Rxd3 Nxe4 22.Rgd1 Rxd3 23.Rxd3 f5 24.f3 Nf6
24...Nc5?! effectively forces a rook-and-pawn ending, but after 25.Bxc5 bxc5 26.Rd5 Ke7 27.Rxc5, I found it hard to believe Black has much chance of holding the ending a pawn down.
25.c5?!
I intended meeting 25.Rd6 with 25...0-0?! (not 25...Kf7?? 26.Rxf6+!), but Stockfish10 gives 26.Bb2 Ne8 27.Rd7 Rf7 28.Rd8 Re7 29.Ba3 Re6 30.Kd3, when Black is tied up. Better, therefore, seems to be the engines' 25...Nd7, although after 26.Re6+ Kd8 27.Bd6 Black is very passive.
25...Kf7
25...bxc5? loses the a pawn after 26.Bxc5.
26.c6
Not 26.cxb6? axb6 27.Rd6 as Black has 27...Ra8, and if 28.Bb2, then 28...Ne8=.
26...Rc8 27.Rd6 Ne8?!
I rejected 27...Rc7?! because of 28.Bb2? Ne8 29.Rd7+, missing that Black is close to winning after the simple 29...Ke6. However, the engines find 28.e4!, eg 28...Ne8 29.e5!
Best, therefore, seems to be pushing the a pawn to a6 or a5 to stop it being vulnerable to the white rook on White's seventh rank.
28.Rd7 Kf6?!
I thought 28...Kg8!?, which is the engines' choice, was simply not active enough, eg 29.Rxa7 Rxc6 30.Kd3, but the engines reckon White only has a slight edge after 30...Nc7.
29.Rxa7?!
Even stronger, according to the engines, is 29.Rxh7 Rxc6 30.Rxa7 Rc2+ 31.Kd3 Rxh2 (not 31...Rxa2?? 32.Be7+) 32.f4!? I guess the point is that White's pieces are much better coordinated than Black's, and anyway rook and bishop is nearly always a better combo than rook and knight.
29...Rxc6 30.Kd3
The engines prefer 30.Rxh7!? Rc2+ 31.Kd3 Rxa2, although the line is not as strong as first capturing on h7, as given in the previous note.
30...Nc7 31.Bb2+ Ke6 32.Bd4 h5?!
I looked at 32...f4! 33.exf4 but rejected it because 33...Kf5?? loses to 34.Be4. However, the engines show that the correct follow-up is 33...Nb5, when the game is equal.
33.Rb7 b5 34.h4 Kd7?
This loses by force. I did not like the look of 34...Kd6 35.f4, eg 35...Kd5 36.Be5, as Black is losing the b pawn, but the engines reckon White is only slightly better thanks to Black's activity in the line 36...Ne6 37.Rxb5+ Nc5+ 38.Ke2 Kc4.
35.Be5 Kc8 36.Rxc7+ Rxc7 37.Bxc7 Kxc7

White to play and win

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38.e4
The engines reckon this wins, but they are wrong, as we shall see.
Correct is 38.Kd4!, which Komodo9 comes to prefer over the text after a short while. Stockfish10 instantly prefers 38.Kd4!, but only by a narrow margin. After 38.Kd4!, best play proceeds 38...Kd6 39.f4 Kc6 40.Ke5 c5 41.Kf6 Kb4 42.Kxg6 Ka3 43.Kxh5 Kxa2 44.Kg6 b4 45.h5 b3 46.h6 b2 47.h7 b1=Q 48.h8=Q Qb6+ 49.Kxf5 Qxe3. White ends the race a pawn up, and can win in 58 moves, according to the Nalimov endgame tablebase.
After the text, White also emerges a pawn up, but this time the position is drawn.
38...fxe4+
Not 38...f4?? 39.e5, nor 38...Kd6?? 39.exf5 gxf5 40.Kd4.
39.Kxe4 Kd6 40.Kf4 Kc5 41.Kg5 Kb4 42.Kxg6 Ka3 43.f4 Kxa2 44.f5 b4 45.f6 b3 46.f7 b2 47.f8=Q b1=Q+
After 38.Kd4!, Black queens first, but the position is nevertheless a win for White. Here White queens first, but Black queens with check and so is in time to avoid Qa8+ etc.
48.Qf5 Qg1+ 49.Kxh5
White cannot win with a rook's pawn, although both engines believe White is winning, and I was able eventually to claim a draw by threefold repetition (½–½, 66 moves)

Mating With B+N: The Stats

COULD you checkmate with bishop and knight against a lone king?
I ask because a Battersea club-mate, who has an ECF of 149, apparently converted the mate with a minimum of fuss in a London Summer League match last week.
When the subject of mating with bishop and knight comes up in conversation, I find many people are either adamant they could do it, or are equally adamant that they could not.
ChessBase's 2019 Mega database has 1,787 examples of the ending, with 368 finishing in a draw. That is a failure rate of 20.6%.
I instinctively felt the failure rate would be higher, but it should be remembered that games that make it into Mega19 are not a genuine cross-selection of all games played.
I have more than 3,600 games in my personal database, with the bishop-and-knight ending appearing only once.

Black to make his 64th move in Spanton (2008) - Michael Shepherd (2071), Isle Of Man 2002

64...Rxg3!? 65.Nxg3
Fifty moves to go.
65...Ke6 66.Ke4
As is well known, the first task of the player with the minor pieces is to force the enemy king to the back rank.
66...Kd6 67.Kd4 Kc6 68.Ba4+ Kd6 69.Bb3 Ke7
During the game, I thought voluntarily retreating like this was very strange. However, 69...Kc6 is no improvement as "back rank" in this ending actually means any edge of the board. So after 69...Kc6, play might proceed 70.Nf5 Kb5 71.Kc3 Kc5 72.Bc4 Kc6 73.Kd4 Kb6 74.Kd5, and Black is successfully being driven to the edge.
70.Ke5 Ke8
Or 70...Kd7 71.Nf5 Kc6 72.Kd4, transposing to the previous note.
71.Nf5 Kf8 72.Kd6 Ke8 73.Ke6 Kf8 74.Kf6 Ke8 75.Nd6+ Kf8
It is usually correct for the defender, once on the back rank, to head for the corner with a square of opposite-colour to the bishop. However, here it was better to leave the back rank with 75...Kd7, which does not save the game but means the mate will take longer.
76.Bc2 Kg8 77.Bg6 Kf8 78.Nf5 Kg8 79.Nh6+ Kf8 80.Bf5 Ke8 81.Be6 Kf8
81...Kd8 allows the black king to escape the back rank, and so prolong the mate.
82.Ng4 Ke8 83.Ne5 Kf8
This time ...Kd8 speeds the mate, viz 83...Kd8 84.Bd7 Kc7 85.Ke6 Kb6 86.Kd6 Ka5 87.Kc5, when the black king is corralled and will soon meet its end on a8.
84.Ng6+ Ke8 85.Ke5 Kd8 86.Kd6 Ke8 87.Bd5 Kd8 88.Bf7 Kc8 89.Ne7+ Kd8
89...Kb7 delays mate by two moves, but, despite my ropey technique, Black is doomed in either case.
90.Nc6+ Kc8 91.Na5 Kd8 92.Nb7+ Kc8 93.Nc5 Kd8 94.Ne6+ Kc8 95.Kc6 Kb8 96.Kb6 Kc8 97.Be8 Kb8 98.Bd7 Ka8 99.Nc7+ Kb8 100.Na6+ 1-0
100...Ka8 101.Bc6# would have meant I mated in 36 moves from the position after 65...Ke6. According to the Nalimov endgame tablebase, I should have been able to do it in 25 moves. I therefore took 44% longer than necessary, which I think shows there is a fair bit of leeway in this ending, so good technique is not always a must!

The Danger Of Not Computer-Checking Analysis

HERE is a fascinating ending that received much (misguided) praise in the December 2000 issue of Chess Life,  the magazine of the US Chess Federation.
The game is from a primary-schools championship held in Norway and, not surprisingly, did not make it into ChessBase's Mega database.
We are told the player of the black pieces was 12 years old and had a national elo of 708 (that converts to an ECF of 1).
He still plays chess today and has a Fide of 1926. His Finnish opponent is also registered with Fide, but does not have an international rating.

Black to make his 51st move in Mikko Salama - Hakon* Astrup

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51...Nxb4??
In the Chess Life article this move gets an exclamation mark. The annotation is credited to "International Master Bjarke Kristenson." I suspect the surname should be Kristensen, as a Bjarke Kristensen was the lead author of Learn Chess From The World Champions: Kasparov-Anand 1995. He seems to have ceased being an active player in 2003, but there is a Fide-registered player called Bjarke Hautop Kristensen, born in 2000 and with a rating of 2223 - maybe his son?
Anyway, Kristensen, as I shall call the Chess Life annotator, commented: "51...Nb4! Sometimes it takes a child to see it! As White's knight is fully employed blocking a pawn, Black can afford to enter a 'king-and-pawn ending' - and still win!"
Kristensen says Astrup rejected 51...Nxe5 because "he wasn't sure how to stop White's pawn in time after 52.b5." Komodo9 and Stockfish10 show Black wins with 52...Nd3 (other moves, including 52...Ke7 and 52...Nd7, also win) 53.c6 (or 53.b6 Nxc5+ 54.Kb5 axb6) Ke7 54.Ka5 Nc5 55.b6 axb6+ 56.Kxb6 Ne6 etc. I am not claiming this was easy to see from the diagram (especially for a player with the equivalent of an ECF grade of 1), but I do not doubt Kristensen could work it out. Incidentally, 51...Ke7 also wins.
In any event, it is clear the move played does not deserve an exclamation mark. Indeed, as the following analysis shows, it should have turned a win into a loss.
52.Kxb4 Ke7 53.Kb5 Kd7 54.Nf3 Kc7 55.c6 a6+
Kristensen also gave this an exclamation mark, but it does not change the assessment of the position as winning for White.
56.Kxa6?
Kristensen does not comment on this move, but now the result should be a draw. White's correct plan was to force the queening of his c pawn, viz 56.Kc5 a5 57.Nd4! h2 58.Nb5+ Kd8! (58...Kc8 loses more quickly, ie 59.Kb6 h1=Q 60.Na7+ Kd8 61.c7+ Ke7 62.c8=Q and, according to the engines, White mates in 11 moves) 59.Kd6 h1=Q 60.c7+ Kc8 61.Na7+ Kb7 62.c8=Q+ Kxa7 63.Qc7+ Ka6 64.Qxf7. White's more-advanced passed pawn means he is winning this queen-and-pawn ending.
56...Kxc6 57.Ka5?
Again Kristensen does not comment, but this loses a tempo and changes a draw into a loss. Correct was 57.Nh2 as 57...Kd5 58.Kb5 Kxe5 59.Kc5 Kf5 60.Kd4 Kxg5 is a Nalimov endgame tablebase draw.
57...Kd5 58.Kb4 Ke4
Kristensen: "Another example of just how poorly a knight can guard a passed h (or a) pawn."
59.Nh2 Kxe5
This draws. Winning was 59...Kf5! (or 59...Kf4!), eg 60.Kc4 Kxg5 61.Kd3 (or 61.Kd4 Kf4) Kf4 62.Ke2 Kg3 (but not 62...Kxe5?? - another tablebase draw) etc.
60.Kc3 Kf4
This is given as 60...Kf5 in Chess Life, but Kristensen's next annotation suggests the text is correct.
61.Kd2 Kxg5
Kristensen gave this an exclamation mark, commenting: "Astrup was (not) fooled by 61...Kg3? 62.Ke3 Kxh2 63.Kf2 Kh1 64.Kf1! with a draw."
Kristensen added this final comment: "In the resulting endgame, Black's three passed pawns slowly but surely outplay White's single knight." Actually, the ending is drawn, although clearly much more fun for Black to play as he is the only one who can hope to win.
62.Ke3 Kh4 63.Kf4 g5+ 64.Kf3 f5 65.Kf2?
White is now losing. The only drawing move was 65.Nf1, when Black cannot make progress, eg 65...g4+ 66.Kf4 h2 67.Nxh2 g3 68.Nf3+ etc.
65...g4 66.Kf1 g3 67.Nf3+ Kg4 68.Ne5+ Kf4 69.Ng6+ Kf3 70.Nh4+ Kg4 71.Ng6 f4 (0-1, 90 moves)
As should go without saying, but I will state it anyway, Kristensen is a much stronger player than I am ever likely to be, but his annotations show how easy it is to get even simple-looking positions drastically wrong without the help of engines (admittedly they were not as strong in 2000 as they are today, but even so …)
*Chess Life has the spelling Haakon, but Fide uses Hakon. This is presumably due to a matter of taste when transliterating from the 29-letter Norwegian alphabet that uses accents.

Hampstead Highlights

IN this post I intend to highlight the moment the result of each of my games was decided in the weekend's five-round Hampstead U2200.
Round One
Spanton (1884/171) - Gavith Dharmasena (1560/154)

White to play and win

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67.Kd5?
This only draws.
Interestingly, the analysis engine Komodo9 reckons the position is drawn, while Stockfish10 assesses it as winning for White. The latter engine is correct, as can be checked with the Nalimov endgame tablebase. The winning method is 67.Nd4 Kc4 (only now does Komodo9 recognise the win) 68.Ke5 (68.Ke3 also wins) Kc5 69.Nf3 Kc4 70.Nd2+ Kc3 71.Nb1+! (the key move, diverting Black's king as far as possible from a8) Kb2 (71...Kc4 does not help as Black's king soon has to give way to White's) 72.Kd4 Kxb1 73.Kc3 Kc1 74.Kb4 Kc2 75.Kxa4 Kc3 76.Kb5, and Black's king cannot reach a8.
The game saw:
67...Kxc2 68.Kc4 Kd2 69.Kb4 Kd3 70.Ka4 Kc4
This is drawn because White's king cannot escape the a file while simultaneously protecting the pawn and keeping Black's king out of a8. The remaining moves were:
71.Ka5 Kc5 72.Ka6 Kc6 73.a4 Kc7 74.Ka7 Kc6 75.a5 Kc7 76.a6 Kc8 ½–½
Round Two
Theodore Slade (2125/no ECF) - Spanton (1884/171)

Black to play and equalise

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20...Nb4?
Correct was 20...g6, which equalises, according to the engines, eg 21.N5d4 Nb4 22.Rd7 Nd3 23.Nf5!? Nxb2, when neither 24.Nh6+ nor 24.e6!? seem to give any appreciable advantage. In any event, 20...g6 was much better than the text.
The game continued:
21.Rd7 Nxa2?
Another mistake, although White is well on top after any continuation.
22.Ng5 (1-0, 52 moves)
Round Three
Spanton (1884/171) - Wolfgang Jekel (1684/148)
I have already covered this game in the post https://beauchess.blogspot.com/2019/06/73rd-hampstead-u2200-round-three.html
Round Four
Ethan Sanitt (1723/159) - Spanton (1884/171)

Black to play and win

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54...c4??
Somehow, in my mind's eye, White's bishop had captured on h7. After the text, White played 55.Bxc4 with an instant draw.
Instead, Black wins easily with 54...Kd3, eg 55.Bxh7 Be5 followed by ...c4 etc.
Round Five
Alex Barlov (1740/154) - Spanton (1884/171)

White to play and win

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45.Bf1
This does not spoil the win but, after making the move, AB pressed his clock and almost immediately offered a draw, which I accepted.
White wins with 45.c5, eg 45...bxc5 46.bxc5 Kd5 47.Bb5 Kxc5 48.Bd7 etc.

Did Black Miss A Draw?

HAD a 64-move rook-and-pawn ending in round three of the Bad Wiessee Senioren-Cup today … and it seems my opponent missed instructive draws on consecutive moves.

The rook-and-pawn ending began with White to make his 28th move in Spanton (1880) - Elof Cordts (1701)

White is about to go a pawn up, leaving Black with four isolated pawns, including two that are doubled.
I certainly thought I was winning, and the analysis engine Stockfish10 agrees. But another very strong engine, Komodo9, 'merely' gives White plus-over-equals - after all, it is a rook-and-pawn ending!
The critical position came 50 moves later:

White has just played 78.Kf4-f5

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78...Ra6
I thought Black had to play 78...Kg7. After 79.Rd7+ Kh6, the first point is that White cannot play 80.Kxf6 as Black draws with 80...Ra4 81.Kf5 Rf4+! (81...Rxg4! also draws). If instead of 81.Kf5, White tries 81.g5+, then 81...Kxh5 is a tablebase draw.
Since 80.Kxf6 does not work, White is more-or-less obliged to try 80.Rf7. Then comes 80...Ra5+ 81.Kf4 (81.Kxf6 is met by 81...Ra4 with a draw as before) Ra4+ 82.Kg3 Ra3+ 83.Kh4 Rf3 84.Rb7 (84.Rxf6+? Rxf6 85.g5+ Kg7 is a trivial draw) Rf1, and there does not seem to be any way for White to make progress.
One line given by the engines after 84...Rf1 goes 85.Rb4 Rh1+ 86.Kg3 f5! 87.Kg2 (87.gxf5 is the notorious drawn ending of f+h pawns) Ra1, and the best White can get is again the drawn f+h pawn-ending.
Where possible I have confirmed the engines' conclusions with the Nalimov endgame tablebase, so it does seem Black missed a draw. It is perhaps needless to say that neither player was aware of virtually any of this during the game.
Going back to the second diagram and the game continuation of 78...Ra6, there followed …
79.Re4 Kg7?
It seems Black still had a draw with 79...Ra1! (or 79...Ra2! or 79...Ra3!). Here the point is that, after 79...Ra1!, White has nothing better than 80.Kxf6, but then Black has a tablebase draw with 80...Rf1+ as the White king has to let its counterpart into g5, after which the draw is relatively simple. No wonder Tartakower (or was it Tarrasch?) quipped that all rook endings are drawn.
After Black's second missed drawing chance, the game finished:
80.Re7 Kf8 81.Re6 Ra4 82.Rxf6+ Kg7 83.h6+ Kh7 84.Rf7+ Kh8
Black meets a swifter end after 84...Kxh6? 85.g5+ Kh5 86.Rh7#
85.g5 Ra8 86.Re7 Kg8 87.g6 Ra5+ 88.Kf6 Ra6+ 89.Re6 Ra8 90.Rd6 Rb8 91.Ke7 1-0

Missed Draw?

MY analysis engines disagree, but I seem to have missed a draw in round two of the Jersey Open today.

Black to make his 43rd move in Brendan-Budok Durand-Le Ludec (2168) - Spanton (1914)

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43...d5?
This made it easy.
Critical was 43...Kd7, which Stockfish10 and Komdo9 reckon also loses after 44.Kf4 Kc6 45.Ke4 b5! 46.Kd4 (the immediate 46.cxb5+ transposes) Kb6 47.cxb5 Kxb5 48.Kd5 Kxb4 49.Ke6! (49.Kxd6 Kc4 is a relatively simple draw) d5 50.Kf7 (50.Kxd5 Kc3 is another simple draw) d4 51.Kxg7. Both engines have had White as winning all the way through this sequence, but the Nalimov six-piece endgame tablebase now shows the position is drawn after any Black move except 51...Ka3 or 51...Kc5.
After the move actually played, 43...d5?, the game continued:
44.cxd5 Kd6 45.f6 gxf6 46.Kf5 Kxd5 47.Kxf6 b5 48.Kg6 Kc4 49.Kxh6 Kxb4 50.Kg5 Ka3 51.h6 b4 52.h7 b3 53.h8=Q 
White wins this ending by the standard technique of checking Black's king until the king is forced to block its own pawn, at which point White's king edges closer, and so on (1-0, 58 moves)

Win Or Draw?

HERE is an interesting rook-and-pawn ending from a super-tournament played in 2001 in the Kazakh capital Astana.

Black to make his 55th move in Shirov - Morozevich

"All rook endings are drawn" is a well-known aphorism by Tartakower, or was it Tarrasch? It certainly sounds more like the former to me.
Anyway, more to the point, is this endgame a win for White or a draw?
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55...Kb4?
This looks natural, but Black lost a second pawn after 56.Rb6+ Kc5 57.Rxh6, and eventually the game.
Later, according to IM Vladimir Barsky and GM Alexander Baburin, writing in the October 2001 edition of Chess Life, Morozevich was told by Ablai Mirzahmetov, president of the Kazakhstan Chess Federation, that children in the audience nearly screamed out the saving move 55...Rxh5! (this draws because 56.Ra5+ Kb4 57.Rxh5 is stalemate).
Morozevich apparently replied: "Next time they should scream louder."
Would I have done better than grandmaster Morozevich? Well, immodest as it may seem, I might well have done as a very similar idea occurred in my game against the Turkish player Burak Akguc (unrated at the time, but now 2120) at the 1997-8 Hastings Challengers'.

White has just played 49.Ke3xf4? in Akguc - Spanton (2065)

BA should have played 49.gxf4! as 49...Rxb4 50.Rxa7 Kxh4 wins for White after the only-move 51.Rh7+, according to the Nalimov endgame tablebase.
After the move played, 49.Kxf4?, the game finished:
49...Rxb4+ 50.Kf5 Rb5+ 51.Kf4
Or 51.Kf6 Rf5+! etc.
51...Rb4+ 52.Ke3 Rb3+ 53.Kf2 Rxf3+! ½–½

Four Juniors And A German

PLAYED at the 69th Hampstead congress over the weekend, scoring +2=1-2.
Hampstead has a time limit of 60mins with a 30sec move-increment - Fide allows such games to be rated, provided no player is over 2200, which is why the congress's three sections are U2200, U1900 and U135ECF.
The fast time-control means that playing three games on a Saturday does not feel anywhere near as tiring as it does with more traditional time controls. Indeed the Saturday 'evening' game starts at 5.30pm and is usually finished before 9pm.
Playing in the U2200, I faced four juniors with a combined age of 50, which was also the age of the one adult, a German, I faced - perhaps something for Jim Plaskett to include in a second edition of his book Coincidences.
My 50% score was a Fide rating performance of 1769.8, meaning I lost 15.6 rating points. That looks pretty bad, although my ECF grading performance was a more respectable 166.4.
In round one I got down to a rook-and-pawn ending for the fourth game in a row.

Black to make his 34th move in Jessica Mellor (1609/145) - Spanton (1906/171)

34...Bxe4 35.fxe4 cxb4 36.axb4
Black's protected passed a pawn means pawn endings will almost certainly be lost for White, but the rook-and-pawn ending is certainly not hopeless.
36...Ke6 37.Rf2 Rf7 38.Rfe2?
But giving up the only open file is definitely hopeless.
I was expecting 38.Rxf7 Kxf7 39.Rf1+. My main analysis engines Komodo9 and Stockfish10 give best play as 39...Kg6 (39...Ke6 40.Rf5 Rg8 looks to be completely drawn) 40.Rf5 a3! 41.Kb1 Kh5 (the reason Black's king went to the kingside - to attack White's kingside pawns).
This position deserves another diagram, as White's next is critical.

What should White play?

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The engines reckon White's rook has to give up its outpost as 42.Ka2!? is met by 42...Rc8, which they reckon gives Black the upper hand. But it is not clear Black can make serious progress after 43.Rf2. The engines give best play as 43...Rc3 44.Kb1 Kg6 (if 44...g4 then 45.Rf5+ Kg6 46.hxg4 a2+ 47.Kxa2 Rxc2+ 48.Kb3 Rxg2 49.Rxe5 Rxg4 [49...h3 transposes] 50.Rxb5 h3 51.Rb8 with dead equality).
After 44...Kg6 the engines still believe Black has the upper hand, but cannot find a line that improves Black's position, eg 45.Re2 g4 46.g3! gxh3 47.Rh2 a2+ 48.Ka1 Rxc2! 49.Rxh3 Kg5 50.gxh4+ Kg4 when after 51.Rh1 White's dangerous passed h pawn is enough to hold the balance.
Going back to the diagram, the engines reckon White needs to give up the outpost by, say, 42.Rf6, but the engines like Black after the reply 42...Rc8, when they sharply disagree on how White should proceed. One line given by Stockfish10, but initially strongly disliked by Komodo9, goes 43.Kc1!? a2 44.Ra6 Rf8 45.Rxa2 Rf2 46.Ra5 Rxg2 47.Rxb5 Rh2 48.Rxe5 Rxh3 49.Rf5 Rh1+ 50.Kb2 h3 51.Rf8 Kg4 52.b5, when it seems White's passed pawn gives sufficient counterplay for a draw.
Given enough time, Komodo9 comes to quite like 43.Kc1!?, but eventually the engines agree on 43.Ra6, with the main line going 43...g4 44.Rxa3 Kg5 45.Ra7 Kf4 46.Rf7+ Kg6 47.Rg7 Kxg2 48.Rxg4+ Kxh3 49.Rg5 Kh2 50.Rxe5. Again it seems White has enough counterplay, eg 50...Rg8 51.Rxb5 h3 52.Rh5 Kg2 53.c3 dxc3 54.Kc2 h2 55.Kxc3 h1=Q 56.Rxh1 Kxh1, and the Nalimov endgame tablebase shows the position is drawn.
These lines are very tricky, with the engines' evaluations frequently changing and often not in agreement. Nevertheless, it is clear 38.Rxf7 was White's best, and probably was enough to draw, if difficult in practice.
Back to the game:
38...Ref8 39.Kb2 Rf1 40.Rxf1 Rxf1 41.c3
This does not help White's cause, but White was out of useful moves, eg 41.Rd2 Kf6 42.Re2 g4 43.hxg4 Kg5 and Black wins on the kingside.
41...dxc3+ 42.Kxc3 Rb1 43.Rb2 Rxb2 44.Kxb2 Kf6 (0-1, 66 moves)