02 April 2012

Stalemate Dangers

Lesson of the Week

There are no school chess clubs meeting this week on account of Spring Break. Even so, for those following this blog, I offer two instructive endings from Saturday's Dragonslayer.

In the first, I was called to the board to mediate a dispute between the players. At issue was the presence of White's second queen. Both players agreed that White had promoted a pawn to a queen on a8, but the player of Black insisted that she had captured the queen with her knight, and then subsequently lost the knight. The White player insisted that he had promoted the pawn after the knight had been captured.

Neither player was writing down the moves, so there was no recourse to the scoresheet. One judge had observed the game, but was the father of the player of White, and so recused himself from the discussion.  I wanted to point out that the extra queen should make no difference in the outcome, but our scholastic rules strongly discourage interference in the games.

After several minutes of "he said, she said," Black conceded the presence of the queen so the game could go on. Both agreed that it was Black's turn.

Black to move

Play continued 1...Kh5 2.Qh8+ Kg6 3.Qaf8 1/2-1/2.

White could have played 2.Qh7# if I had disallowed the second queen. With both queens on the board, 2.Qh1# was also possible.

The second tragicomedy occurred in a game between two of the strongest players in the elementary section.

Black to move

Play continued 1...Ke8 2.Ke6 Kf8 3.f7 Kg7 4.Ke7 Kh7 5.f8Q 1/2-1/2.

White has a clear advantage in the diagram position, but there are drawing dangers. If the h-pawns were absent, the game would be drawn with correct play. In principle, I would have played Black as if these pawns were absent. Engine analysis confirms that these moves are best, when "best" is measured as the longest sequence leading to mate. On the other hand, Black's sub-optimal moves may have been the best strategy psychologically.

1...Kf8 2.Ke6 Ke8 3.f7+ draws
1...Kf8 2.Kf4!+-

In the game, 5.f8R wins. 5...Kg7 6.Rf6 Kh8 7.Kf7 Kh7 8.Re6 Kh8 9.Rxh6#.

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