Lessons From Cap Negret VIII

I HAVE been asked a couple of questions about the ending in my round-eight game, where I had white against fellow Battersea Chess Club member Paul Stokes (1807).

The first question arises in the following position, where I have just played 65.Rc7-c5.

Black replied 65...Bf3?, but in my blog notes I pointed out that Stockfish17.1 and Dragon1 reckon both 65...Kg7 and 65...Kh7 hold

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First, let us see what happened in the game.

I played 66.Bd7!, to which Black gave a check with 66...Rb1+, only to resign after I continued 67.Kf2.

The point is that after 67...Be4 68.Bd5+, Black is losing a second pawn, giving White two protected passers.

I was asked, why does 65...Kg7 make such a difference, particularly as White is poised to win a second pawn anyway, eg with 66.Bc6? The point is that, with the black bishop on a secure square, 66...Rb1+ now draws, one line running 67.Kf2 Rb2+ 68.Kg3 Rb3 69.Bxd5 Rxe3+ 70.Kf2 Rf3+ 71.Ke2 Bxd5 72.Rxd5 Rf4 etc.

The second question concerns this position, after 66.Bd7!

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In my notes I covered what happens if, instead of checking with the rook by playing 66...Rb1+, Black secures the bishop with 66...Be4. The engines reckon 66...Be4 is probably Black's best try, but 67.Bc6 wins, eg after 67...Rb1+ 68.Kf2 Rb2+ 69.Kg3 Rb3 the same position is reached as in the previous note, except the black king is on g8 rather than g7. That makes all the difference as capturing on d5 now comes with check, and after 70.Bxd5+ Bxd5 71.Rxd5 Rxe3+ 72.Kf2 Black does not have ...Rf3+, and the rook-and-pawn ending is an easy win for White, according to the engines.

I was asked, doesn't 66...Rb2, rather than the checking 66...Rb1+, draw? After 67.Be6+ Kf8 68.Bxd5, this seems correct, as both 68...Bxg4, and 68...Re2+ followed by 69...Bxg4, give excellent drawing chances. However, the engines point out the strength of 68.Rc7! (other moves also apparently win), when Black can no longer capture on g4. Black could try 68...Re2+ 69.Kf1 Rxe3, but 70.h6 (even stronger than the also-winning 70.Rf7+) is decisive, eg 70...Be4 71.Rc8+ Ke7 72.Bf5 Bxf5 73.gxf5 Rh3 74.h7 Rxh7 75.Rc7+ etc.

LESSON: engine analysis, especially when options are relatively few, is nearly always correct, but a lot can be learnt by delving into what lies behind the engines' verdicts.