Nimzo-Indian Defense: St. Petersburg Variation 8…f5 9. O-O
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Statistics from Lichess
33,205 games: White 44.3% / Draw 5.6% / Black 50.1%
| Next move | Games | White / Draw / BlackW / D / B |
|---|---|---|
| 26,22326K | ||
| 5,6785,678 | ||
| 392392 | ||
| 194194 | ||
| 175175 | ||
| 166166 | ||
| 8383 | ||
| 7373 |
Rated Lichess games between players rated 1600 to 2500, from the Lichess opening explorer, updated Nov 5, 2026
Engine evaluation
+0.27 The position is about equal
Best play: 9... O-O 10. Nd2 Qh4 11. f3 Nxd2 12. Bxd2 d6 13. Be1 Qe7 14. a4
Stockfish 19, depth 30, after the line's last move. Scores are in pawns, from White's side.
Overview
Nimzo-Indian Defense: St. Petersburg Variation (ECO E43, Indian Defenses) is a variation of the Nimzo-Indian Defense: St. Petersburg Variation, reached after 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Nf3 b6 5. e3 Ne4 6. Qc2 Bb7 7. Bd3 Bxc3+ 8. bxc3 f5 9. O-O (9 moves).
In 33,205 rated Lichess games between players rated 1600 to 2500, White won 44.3%, Black 50.1% and 5.6% were drawn. Black's most played move here is 9…O-O, in 79% of those games.
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How to answer 9. O-O
The most played answer, 9…O-O, also scores best for Black: 54.0%, with Black winning 51.1% and White 43.2% of 26K games. Of the main answers, 9…d6 scores lowest: 50.2%. Stockfish's first choice is also 9…O-O.
Main answers: those played in at least 5% of these games. Score: Black'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. “Nimzo-Indian Defense: St. Petersburg Variation (E43)”. Lichess data as of 5 Nov 2026. https://chesscodex.org/openings/nimzo-indian-defense-st-petersburg-variation-11