Alekhine Defense: O'Sullivan Gambit
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Statistics from Lichess
158,253 games: White 43.7% / Draw 3.4% / Black 52.9%
| Next move | Games | White / Draw / BlackW / D / B |
|---|---|---|
| 90,89391K | ||
| 30,71231K | ||
| 13,82914K | ||
| 10,39010K | ||
| 4,1194,119 | ||
| 2,0432,043 | ||
| 1,3321,332 | ||
| 833833 |
Rated Lichess games between players rated 1600 to 2500, from the Lichess opening explorer, updated Oct 31, 2026
Engine evaluation
+2.13 White is clearly better
Even so, Black scores 54.6% here in practice: wins plus half the draws in rated Lichess games between players rated 1600 to 2500.
Best play: 4. Bxb5 c5 5. c4 cxd4 6. Qxd4 Nb4 7. Qd1 Qc7 8. a3 N4c6
Stockfish 19, depth 30, after the line's last move. Scores are in pawns, from White's side.
Overview
Alekhine Defense: O'Sullivan Gambit (ECO B03, Semi-Open Games) is a gambit in the Alekhine Defense, reached after 1. e4 Nf6 2. e5 Nd5 3. d4 b5 (3 moves).
In 158,253 rated Lichess games between players rated 1600 to 2500, White won 43.7%, Black 52.9% and 3.4% were drawn. White's most played move here is 4. Bxb5, in 57% of those games.
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How to play against the Alekhine Defense: O'Sullivan Gambit
4. c4 scores best for White: 55.4%, with White winning 53.5% and Black 42.7% of 14K games. The most played, 4. Bxb5, scores 43.5% in 91K games, and 4. f4 scores lowest: 42.5%. Stockfish's first choice is 4. Bxb5.
Main answers: those played in at least 5% of these games. Score: White's wins plus half the draws, in rated Lichess games between players rated 1600 to 2500. How to play against other popular openings
Cite this page
Caissa Codex. “Alekhine Defense: O'Sullivan Gambit (B03)”. Lichess data as of 31 Oct 2026. https://chesscodex.org/openings/alekhine-defense-osullivan-gambit