Test your chess: daily chess puzzle # 20

White to play and win

CH Van der Meyden v R Rubin 1962

Solution

Consider all biffs requires that 1 Nf6+! is looked at, and there really is only one line: 1…gf (though 1…Kf8 is best met not by 2 Nd7 but by 2 Qe8+ proceeding as in the main line) 2 Qe8+! Re8 3 Re8+ Qe8 4 Bd6 and black can't prevent the pawn from promoting. (I should add that when as is my way of writing these blogs, then entering the positon into Stockfish, it prefers 4 Bf7+ first, and of course the machine is right- a pawn is a pawn).

White emerge a piece up.

For fairness to Stockfish, I should add that it evaluates the above position as +3.6, or the position after its 4 Bf7+ as +3.9, whereas it actually prefers 1 Qa6, at +6.5. Apparently after 1…cd 2 Nd6 Re1 3 Ke1 black can't prevent the b7 pawn from being promoted, save by giving up the rook: but 1 Qa5 keeps more pieces on, at least initially, has more complexity, and is thus less 'human'.

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