Lessons From Transylvania VI

IN round seven of the Brașov International (I missed round six through being in hospital) I had black against a 1932.
The full game can be seen at B7 but here I want to concentrate on key moments in the middlegame.

White has just gained space in the centre with 17.e5

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17...Bxg2

Stockfish15 and Komodo13.02 prefer 17...Nd5!? 18.Nxd5 Bxd5 19.Bxd5 exd5, which, like the text, exchanges off White's powerful light-square bishop but leaves Black with an isolated queen's pawn. Then 20.Bf4 gives White a slight edge, according to the engines.

18.Kxg2

Almost certainly not 18.exf6?! Qc6 (18...Bh3?! 19.fxg7 Rfd8 20.Ne4) 19.Qg4 g6.

18...Nd7

The engines prefer 18...Nd5 19.Nxd5 exd5, reaching the same position as in the note to Black's 17th, move except the white king is on g2 rather than g1.

19.Bf4

Even stronger, according to the engines, is 19.Rac1!?, eg 19...Qxb2 20.Na4 Qxa3 21.Qb5 Nxe5 22.Bc3! Bd4 23.Ra1 Qd6 24.Bxd4 Qc6+ 25.Qxc6 Nxc6 26.Be3, a sharp line that leaves White with a bishop and the superior development for three pawns.

How should Black respond?

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19...Bd4

The engines do not like this, but cannot agree on what should be played. One line given by Stockfish15 runs 19...Qc6? 20.f3 a5 21.Ne4 b6 22.h4, when it reckons White is positionally winning. Komodo13.02 suggests 19...Rfd8 20.Bg5 f6 21.exf6 Nxf6 22.Bxf6 gxf6 23.b4 Qc6+ 24.Ne4!? f5 25.bxc5 Rxd1 26.Rxd1 Qxe4+ 27.Qxe4 fxe4 28.Rd4, claiming a large advantage for White in the rook-and-pawn ending.

White to play and win

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20.Kg2?

This lets Black equalise. Best seems to be 20.Nb5!? Bc5 21.Rac1 (21.Rxd7?? Qc6+) Rac8 22.b4 Be7 23.Be3, eg after 23...Qd8 24.Bxa7 White is a pawn up with the much better position, and trying to trap the white bishop with 24...b6 can be met by 25.Qe4 (other moves are also strong, according to the engines), when 25...Ra8 gets nowhere after 26.Rc7 or 26.Qb7.

Also good, according to the engines, is 20.Rac1 Bxc3 21.Rxc3, when Black seems to have nothing better than the deeply unpleasant 21...Nb8 as 21...Rad8 (or 21...Rfd8) loses to 22.Rd6 Qa5 23.b4 Qa4 24.Rcd3 etc.

After the text the game quickly simplified into a draw:

20...Bxc3 21.Rxd7 Qxb2 22.Qxb2 Bxb2 23.Ra2 Bc3 24.Rc2 Ba5 25.Rxb7 Rfb8 26.Rxb8+ Rxb8 27.Be3 Bb6 28.Bxb6 axb6 29.Rc7 ½–½