Starting position
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-0.97
Explain Your Games
We use our method, BinProp, to explain mistakes made by Magnus, Hikaru, and other top players. You can move pieces on the board, reset the position, or input your own games to get explanations.
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-0.97
Vladimir Fedoseev vs Magnus Carlsen · June 19, 2014
Magnus played Nf8, but Stockfish prefers Qxa3.
22. Bxc3
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Why Qxa3 beats Nf8
Qxa3leads to:
Present afterQxa3
Black's pieces have greater mobility: Black has 40 legal moves, including 14 with the queen on d6; White would have 36 legal moves if it were White's turn.
Absent afterNf8
Present afterQxa3
White has permanent weak squares on g3 and b4 that its pawns can no longer challenge.
Absent afterNf8
Present afterQxa3
All of Black's major and minor pieces are secure: knights on b6 and d7, rooks on d8 and e8, and queen on d6. None is undefended under attack or attacked by a cheaper White piece, and White has no safe one-move attack with a cheaper piece against any of them. The development requirement is met by Black's knight on b6 and queen on d6.
Absent afterNf8
Nf8leads to:
Starting position
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h8
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+0.18