Why does Fritz prefer underpromotion in this position? How can underpromotion to bishop evaluate so much higher than normal queen promotion?
Can this be a bug in the Fritz 14 chess engine?
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Sign up to join this communityWhy does Fritz prefer underpromotion in this position? How can underpromotion to bishop evaluate so much higher than normal queen promotion?
Can this be a bug in the Fritz 14 chess engine?
It's because 1. exf8=Q+ Kxh7 2. Rxd7??
would be stalemate. I think it is a even a theoretical draw after 1. exf8=Q+ Kxh7 2. Qg7+
. Therefore 1. exf8=B+!
(with check!) is better, since white then can keep an extra piece and win easily.
[FEN "5r2/3qPbkB/8/7P/8/8/8/1K1R4 w - - 0 1"]
1. exf8=Q+ (1. exf8=B+!) Kxh7 2. Rxd7? (2. Qg7+)