Starting from 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 Nc6 6.Bg5 e6 7.Qd2 a6, players enter the Sicilian Defence: 1.e4 c5 2.Nf3... a6 — ECO B66. Lichess records 146,775 games in this line, which gives us a reliable view of how it actually performs in practice.
History and Notable Players
It arises from the Sicilian Defence: 1.e4 c5 2.Nf3... 7.Qd2. Among the most prolific White practitioners are Semen I Dvoirys (41 games), Thomas Luther (39 games), Oleg Korneev (36 games). Black-side regulars include Zdenko Kozul (188 games), Istvan Csom (74 games), Konstantin Z Lerner (69 games).
Performance Across Rating Levels
Popularity and results vary sharply by rating level. The 1200 bracket has 535 games (0.00% of all games at that level); White wins 52%, Black 44.7%, 3.4% are drawn. At 1800 the opening surfaces in 0.00% of games; White wins 49.4%, Black 45.7%, draws 4.9%. At the top end (2500+ Elo), popularity is 0.17% with 8.4% draws — a clear sign of how much theory rules the line at master level. White's edge erodes by 6.0pp from 1200 to 2500 Elo, suggesting Black's counterplay is easier to find with experience.
Move Diversity and Theory Depth
What players actually play after the opening moves depends heavily on rating. At 1200 Elo, the top reply is O-O-O, played 74.2% of the time. There are 2 other moves seeing meaningful share, and 89.1% of games stick to established theory. Entropy: 1.50. By 2500, O-O-O dominates at 90.7% of replies; only 1 viable alternatives remain and 97.2% of moves are theory. Entropy drops to 0.63. That entropy collapse is the signature of a line where preparation pays off: at the top, players know the best move and play it.
Main Lines and Variations
The main branches off 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 Nc6 6.Bg5 e6 7.Qd2 a6 include:
Each branch leads to a different middlegame character — the resulting pawn structure decides what kind of game you get.
Common Mistakes
- Neglecting development — It can feel productive to make extra pawn moves early, but falling behind in piece development is what loses most amateur games — especially in open positions where active pieces find squares fast.
- Ignoring the kingside attack — In sharp Sicilian lines, White typically castles long and pushes the h-pawn. Without your own counterplay on the queenside or in the centre, White's attack lands first.
Practice on Chessiverse
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