Kasparov's Immortal · 1999
59% of club players play Qb2+ here — and it throws away 2.3 pawns
3r3r/1R3p1p/p4Qp1/1p6/1Pq5/k4PPB/2P4P/1K6 w - - 0 3259% of players rated around 1500 play Qb2+
in this position. It is the natural move, and it is not the best one.
| Move | Played by | Evaluation |
|---|---|---|
Qb2+ the reflex | 59% of 1500-rated humans | -6 centipawns |
Qxa6+ the move | 36% | +224 centipawns |
The difference is 2.3 pawns — a back-rank mate threat.
How this was checked
The evaluations are Stockfish. The human percentages are
Maia, a neural network trained on millions of human games and
conditioned on rating — so 59% of players around 1500
is a measurement of what people
actually do, not an estimate of what they might. Any tactical motif named above is verified against
the board geometry rather than described.
Paste a chess.com game you played and ChessCast makes a 10-20 minute coaching podcast about it — two hosts on the audio, and a board that moves in lock-step so you can watch the moment it turned. Every claim is checked against Stockfish before it is spoken.