Wednesday, 3 June 2020

More Lockdown Chess

I AM playing on board three for Lean Thinkers in division two of the 6th British Webserver Correspondence Championship, where the format is six games as a single-round-robin.
My first two games to finish were draws, and I won the next on the black side of a Maróczy Bind (https://beauchess.blogspot.com/2020/05/lockdown-chess.html).
Here is the fourth game to finish.
Spanton (2256) - John G Cooper (2136)
Sicilian Bb5(+)
1.e4 c5 2.Nf3 Nc6 3.Bb5 Nf6
More popular are 3...g6, 3...e6 and 3...d6 but there are 3,700 examples of the text in ChessBase's 2020 Mega database. Richard Palliser in The Bb5 Sicilian (Everyman Chess 2005) called it "the fashionable line."
4.Qe2
More popular, and scoring a higher percentage in Mega20, are 4.Nc3, 4.e5 and 4.Bxc6. The text is not liked by the analysis engines Stockfish11 and Komodo11.01 but has some interesting points.
4...g6 5.c3 Bg7 6.d4 cxd4 7.cxd4 d5
A standard Black response when White gets pawns abreast in the centre.
8.e5 Ne4 9.0-0 0-0 10.Nc3 Bf5
The obvious alternative is 10...Nxc3 11.bxc3, after which Roland Ott (2225) - Evgeny Sveshnikov (2510), World Students Team Championship (Caracas, Venezuela) 1976, continued 11...Na5 12.Bg5 h6 13.Bd2 Bd7 14.Bd3 with an equal game, according to the engines (½–½, 29 moves).
11.Bxc6!?
Giving up the bishop-pair without being provoked by, for example, ...a6, may seem a little strange, especially as White is left with a bad bishop (an old rule of thumb has it that when you have a bad bishop you should not give up your good one), but the move has been played by David Bronstein and Levon Aronian.
11...bxc6 12.Nh4
This was Aronian's choice last year at the Fide World Cup in a draw against Quang Liem Le. Bronstein preferred 12.Na4 in the 1975 Soviet Championship against Vitaly Tseshkovsky, a game that also ended in a draw.
12...Nxc3
Le played 12...e6.
13.bxc3 Bc8
Black has the bishop-pair, and White has a bad bishop. But in the middlegame, I believe I am right in saying, what counts is not so much whether a bishop is good or bad but whether it is active or inactive. Here White is able to activate his one bishop on the a3-f8 diagonal. Meanwhile White has more space in the centre, which should probably also eventually mean more space on the kingside.
14.Ba3 Qa5!?
This is the engines' choice, narrowly over 14...Re8, but White's rather obvious reply makes the move seem odd to me.
15.Bb4 Qc7 16.Bc5 a5 17.Rfe1 f6!?
Black's dark-square bishop, although technically good (Black's d pawn is on a light square), is biting on granite, so the text is an attempt to give it a more-active role and at the same time undermine White's centre. Consistent with Black's previous move is 17...Ba6, but then the engines reckon 18.Qc2, possibly with f4-f5 to come, is good for White.
18.Qe3 fxe5 19.dxe5
We now have a position with rival pawn-majorities, which usually favours the bishops. But here Black's queenside majority is blockaded while White's kingside majority is free to advance.
19...Rb8 20.Nf3 Rb2
This is Komodo11.01's choice. Stockfish11 also likes it at first but comes to prefer 20...Rf5.
21.h3
Partly luft for the king but also keeping the light-square bishop out of g4.
21...Rb5!?
A point behind this is revealed in the note to Black's next move.
22.a4 Rb2
Black may have intended 22...Bh6!? After 23.Qxh6 Rxc5 Black has given up the bishop-pair but broken the blockade on his queenside. The engines reckon White has the upper hand after 24.Re3, and it has to be said Black's king looks unsafe. However I was also considering sacrificing the queen with 23.axb5!? Bxe3 24.b6, which I may well not have had the courage to do over the board, but one can look more deeply at the ramifications when playing correspondence chess.
23.Rab1 Rxb1 24.Rxb1 Bf5 25.Re1 Qd7
The engines give 25...h5 26.Nd4 Kh7 but with a large advantage for White. It seems Black, without making any obviously bad moves, has slowly slipped into a very difficult position.
26.Nd4
Black's queenside is now firmly blockaded, and Black apparently has no counterplay against White's coming kingside expansion.
26...Qb7 27.g4 Bc8 28.f4 Bh6
Komodo11.01 at first reckons this move equalises, but soon comes to agree with Stockfish11's assessment of a large edge for White.
29.Rf1 Rf7 30.e6 Rf8 31.Kg2 1-0
Resignation might seem premature, and I am sure JC would have carried on in an over-the-board game, but the engines agree White is roughly the equivalent of a piece up.

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