Beware of Endgame Checkmates!
The topic of today's article is checkmating ideas in endgames. The inspiration for the article was a recent game played in the Biel tournament, Nakamura vs. Bologan. This article features that game at the very end, first introducing relevant examples from recent practice. In all of the following positions one of the sides unexpectedly started to attack with minimal material present at the board. Usually, the defending side had the king in the center, which is usually an advantage in endgames but as these positions show it can be a disadvantage too.
The position below is about equal - the weaknesses on d4 and g5 compensate each other. The White queen is just a bit better than the Black one because it attacks the g5 pawn as well as playing a defensive role. Wang Hao's plan might be to surround the g5-pawn, while Nepomniachtchi's would be to undermine White's central pawns with a timely c5 or f6 break. These breaks will free the Black queen from the pointless task of staring at the e5-pawn. If you ask me which side I would prefer to play, I would choose White because at this given moment the plan is fairly simple and there is a low chance for a mistake. Let us proceed to the game.
Wang Hao played the endgame brilliantly! Nepomniachtchi played well but made one mistake that resulted in a position where it was very hard to defend. The Kf8-Ke7 maneuver on move 41 is extremely hard to spot and then evaluate correctly. To me it looks almost unbelievable that Black does not have a defense after 41...f6. White has a rook and queen participating in the attack and also one can count the e5 pawn as it takes away the important f6-square. Black has the queen as a defender but the rook cannot participate in defense. If you look at the 8th-rank there are no defenders and White uses it for checkmating threats.
In the next example White is a up whole piece and a pawn (which is a passed pawn). Black built a battery on the f-file and has brought the king up to g5. The king is stalemated and it only takes one check for a checkmate. Therefore, it is extremely tempting to play Qb4 with a threat of Rg4, and it seems that Black can do very little to defend against it.
Black's successful defense is due to well-coordinated pieces and king activity. It is very important to pay attention to opponent's resources even in "easily" winning positions.
The following position might as well be a future tabia of the Bg5 Najdorf-- who knows where modern theoretical highways are taking us. The computer's evaluation is equality, which might be true if Black makes a few precise non-losing moves. Looking from a long-term perspective Black has two bishops, while White has a pawn majority on the queenside. From a short-term look Black is a bit behind in development, as White has the knight and the rook in the game, while Black has only the bishop on b7 developed. Black has to be careful in solving development problems.
Ba6 is unexpected but a player of such caliber as Wang Hao has enough intuition to feel that Ka7 is a bad move. I bet if the game was played in blitz, where one relies more on intuition it would have ended in a draw after Kc7.
Finally, we get to our cover story, Nakamura's win over Bologan. The endgame is long and grueling. Both players for a long time played very well. In the starting position Nakamura is up an exchange for not much compensation. He just needs to get open files for his rooks and the game should end in his favor. However, Bologan managed to find defensive resources connected with king activation. Nakamura kept his rook passive for a long time but when the time trouble approached he brought them to the 1st and the 2nd-rank. Only with active rooks does Black have a chance for a win. But because the rooks no longer defend the Black king Bologan got attacking ideas too. The game became extremely sharp and all three results were possible. Bad luck for Bologan to run into a checkmate, but strong and aggressive play by Nakamura paid off.
Next week we will look at endgames from the recent Washington International tournament, where I participated.