Colle System: Siroccopteryx Variation
1. d4 g6 2. Nf3 Bg7 3. e3 c5 4. Bd3 cxd4 5. Nxd4 Qa5+
6. Nc3+0.18
The position is roughly equal. Stockfish 18, depth 18.
Analyze this positionIn the Colle System: Siroccopteryx Variation (A40), reached after 1. d4 g6 2. Nf3 Bg7 3. e3 c5 4. Bd3 cxd4 5. Nxd4 Qa5+, Stockfish 18 recommends 6. Nc3 for White. The position is roughly equal (+0.18).
Top engine moves
- +0.186. Nc3 Nf6 7. e4 d6 8. Nb3 Qc7 9. O-O Nc6 10. Bg5 Be6
- +0.156. Bd2 Qd8 7. c4 Nc6 8. Bc3 Nxd4 9. exd4 d5 10. O-O Nh6
- −0.016. Qd2 Qxd2+ 7. Bxd2 Nc6 8. Bc3 Nf6 9. Nxc6 bxc6 10. f3 d6
Frequently asked questions
What is the best move in the Colle System: Siroccopteryx Variation?
After 1. d4 g6 2. Nf3 Bg7 3. e3 c5 4. Bd3 cxd4 5. Nxd4 Qa5+, Stockfish 18 at depth 18 recommends 6. Nc3 for White, continuing Nf6 7. e4 d6 8. Nb3 Qc7 9. O-O Nc6 10. Bg5 Be6. The position is roughly equal (+0.18). The next best moves are 6. Bd2 (+0.15) and 6. Qd2 (−0.01).
Is the Colle System: Siroccopteryx Variation a good opening?
Stockfish rates the position at +0.18: the position is roughly equal. Evaluations this early in the game are small, so practical results depend far more on knowing the plans and typical structures than on the engine's number.
What is the ECO code of the Colle System: Siroccopteryx Variation?
A40. ECO codes classify chess openings from A00 to E99; A is the volume for flank openings.
Opening names from the Lichess opening book (CC0). Pieces by Colin M.L. Burnett (GPLv2+).