French Defense traps: the most-played mistakes
6 mistakes actually played in the French Defense, each verified by the engine: the position is playable before, the punishment wins material, and the player share comes from real Lichess games.
Method: Stockfish screening (depth 14 then 22), refutation = best engine moves. Frequencies: real Lichess games 1400-2200+, blitz, rapid and classical. Whatever failed verification is not published.
- Nxd4 ?6.2% of players51,430 games
You centralize your knight, but White's Bd3 captures it with tempo, attacking your queen! After Bc5 Nb5 a6, you're behind in development and your queen must run.
Punishment: Nxd4 Bc5 Nb5 Bd7 Nd6+
+3 points of material, evaluation 3.5 after the punishment.
- f6 ?10.2% of players20,688 games
Weakening your king with f6 is a serious mistake. After Qh5+ g6, Nxg6 wins material and your king faces immediate mating threats.
Punishment: Qh5+ g6 Nxg6 hxg6 Qxh8
+3 points of material, evaluation 3.2 after the punishment.
- cxd4 ?5.5% of players4,486 games
You fatally weaken your kingside by taking the pawn. After Qxg7 Kd7 Qxh8, White raids your pieces and you're crushed. Play Ne7 instead, much sounder.
Punishment: Qxg7 dxc3 b3 Qe7 Qxh8
+3 points of material, evaluation 3.2 after the punishment.
- Nxd2 ?5.9% of players3,468 games
Capturing the bishop weakens your king without compensation. After Qxg7, you lose the rook on f8 and your king stays exposed in the center; you can't hold it.
Punishment: Qxg7 Rf8 Kxd2 c5 Nf3
+4 points of material, evaluation 2.4 after the punishment.
- a6 ?5% of players2,514 games
You weaken your king and abandon your knight for nothing. After Nxc7+ Kd8 Nxa8, you've lost the rook with no play; Nb6 challenges the knight immediately.
Punishment: Nxc7+ Kd8 Nxa8 Qb4+ c3
+6 points of material, evaluation 4.4 after the punishment.
- c5 ?6.3% of players1,371 games
Playing c5 weakens your center and kingside dangerously. After Bxd8 cxd4 Nxd4 Kxd8, you lose your queen for nearly nothing and your king gets trapped in the middle of the board: a disaster!
Punishment: Bxd8 Kxd8 Ng5 Kc7 Nxf7
+7 points of material, evaluation 5.8 after the punishment.