Sicilian Defense: Big Clamp Formation
1. e4 c5 2. d3 Nc6 3. c3 d6 4. f4
The Sicilian Defense: Big Clamp Formation is a chess opening classified as ECO B20, reached after 1. e4 c5 2. d3 Nc6 3. c3 d6 4. f4. It is a line of the Sicilian Defense. Black is to move.
In 12.6 million rated Lichess games (blitz and slower), this position was reached 53 times by this move order. White won 51%, 4% were drawn and Black won 45%. The most popular continuation is 4… g6 (34% of games).
Engine evaluation: 0.00 (Stockfish, depth 42; best line 4… g6 5. a4 Nf6 6. Be2 Bg7 7. Nf3)
- ECO
- B20
- Moves
- 7 plies
- FEN
r1bqkbnr/pp2pppp/2np4/2p5/4PP2/2PP4/PP4PP/RNBQKBNR b KQkq - 0 4- PGN
1. e4 c5 2. d3 Nc6 3. c3 d6 4. f4
Analyse with Stockfish · Board image (SVG) · Open on Lichess
Results by rating
| Average rating | Games | White / draw / Black |
|---|---|---|
| 0-1499 | 14 | |
| 1500-1999 | 31 | |
| 2000+ | 8 | |
| All | 53 |
Most played moves
| Move | Games | White / draw / Black |
|---|---|---|
| 4… g6 | 18 (34%) | |
| 4… Nf6 | 15 (28%) | |
| 4… e6 | 8 (15%) | |
| 4… e5 | 6 (11%) | |
| 4… Bg4 | 3 (6%) | |
| 4… Bd7 | 2 (4%) | |
| 4… Qc7 | 1 (2%) |
Master games
1 over-the-board game is classified under this line (White 0%, draw 0%, Black 100%). The strongest:
- Joachim Huebscher (1796) – Frank Niehaus (2214) 0-1 · Werner-Ott-Open 2015 · 2015-07-11
Search all games of the Sicilian Defense: Big Clamp Formation and its sub-variations
Highest-rated Lichess games
- FM Igor_Perelygin (2478) – Gwaters-2011 (2300) 1-0 · 2026-09-05 · 180 + 2s
- EmersonAttack (2307) – mohamed2morsy (2207) 0-1 · 2026-09-01 · 180 + 0s
- atyaa93 (2112) – grv48 (2193) 1-0 · 2026-09-05 · 600 + 0s
Comes from
Sicilian Defense (1. e4 c5) 1. e4 c5
More Sicilian Defense lines (all)
- Sicilian Defense: Amazon Attack B20
- Sicilian Defense: Bowdler Attack B20
- Sicilian Defense: Brick Variation B20
- Sicilian Defense: Czerniak Attack B20
- Sicilian Defense: Czerniak Attack, Queen Fianchetto Variation B20
- Sicilian Defense: Euwe Attack, Prins Gambit B20
- Sicilian Defense: Gloria Variation B20
- Sicilian Defense: Grob Variation B20
- Sicilian Defense: Keres Variation B20
- Sicilian Defense: King David's Opening B20
- Sicilian Defense: Kronberger Variation B20
- Sicilian Defense: Kronberger Variation, Nemeth Gambit B20
Opening names and moves from the Lichess openings dataset; statistics from the Lichess open database, 2026-09 (CC0), sample of 12.6 million games, bots excluded; evaluations from Lichess cloud analysis (all CC0). Master games from The Week in Chess #920–#1664 by Mark Crowther, used with permission.