Sicilian Defense: Four Knights Variation
1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 Nf6
The Sicilian Defense: Four Knights Variation is a chess opening classified as ECO B45, reached after 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 Nf6. It is a line of the Sicilian Defense. White is to move. 4 named lines continue from this position.
In 12.6 million rated Lichess games (blitz and slower), this position was reached 1,159 times by this move order. White won 46%, 5% were drawn and Black won 49%. The most popular continuation is 6. Be3 (28% of games).
Engine evaluation: +0.35 (Stockfish, depth 55; best line 6. Nxc6 bxc6 7. e5 Nd5 8. Ne4 Qc7)
- ECO
- B45
- Moves
- 10 plies
- FEN
r1bqkb1r/pp1p1ppp/2n1pn2/8/3NP3/2N5/PPP2PPP/R1BQKB1R w KQkq - 3 6- PGN
1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 Nf6
Analyse with Stockfish · Board image (SVG) · Open on Lichess
Results by rating
| Average rating | Games | White / draw / Black |
|---|---|---|
| 0-1499 | 97 | |
| 1500-1999 | 605 | |
| 2000+ | 457 | |
| All | 1,159 |
Most played moves
| Move | Games | White / draw / Black |
|---|---|---|
| 6. Be3 | 323 (28%) | |
| 6. Nxc6 Four Knights Variation, Exchange Variation | 170 (15%) | |
| 6. Bg5 | 169 (15%) | |
| 6. Ndb5 | 119 (10%) | |
| 6. Be2 | 87 (8%) | |
| 6. f3 | 83 (7%) | |
| 6. Bc4 | 54 (5%) | |
| 6. a3 | 45 (4%) |
Master games
760 over-the-board games are classified under this line (White 41%, draw 25%, Black 34%). The strongest:
- Reckless 0.10.0-dev-b5462f11 (3763) – Stockfish dev-20260318-d173a06 (3807) 1/2-1/2 · TCEC 29 Superfinal 2026 · 2026-04-02
- Stockfish dev-20260318-d173a06 (3807) – Reckless 0.10.0-dev-b5462f11 (3763) 1-0 · TCEC 29 Superfinal 2026 · 2026-04-02
- LCZero 0.30-dag-a9b25c2b-BT2-3 (3598) – Stockfish dev-20230409-b36d39d (3639) 1/2-1/2 · TCEC 24 Superfinal 2023 · 2023-04-24
- Stockfish dev-20230409-b36d39d (3639) – LCZero 0.30-dag-a9b25c2b-BT2-3 (3598) 1-0 · TCEC 24 Superfinal 2023 · 2023-04-24
- GM Nodirbek Abdusattorov (2767) – GM Praggnanandhaa R (2767) 0-1 · 2nd UzChess Cup Masters · 2025-06-27
Search all games of the Sicilian Defense: Four Knights Variation and its sub-variations
Highest-rated Lichess games
- IM beatles_21 (2767) – CM Romaa2011 (2790) 1/2-1/2 · 2026-09-03 · 180 + 0s
- FM Buyofl (2716) – CM Romaa2011 (2770) 0-1 · 2026-09-03 · 180 + 0s
- Fettywapest (2721) – CM Mikkel_Vinh (2701) 0-1 · 2026-09-01 · 180 + 0s
Comes from
Sicilian Defense: Taimanov Variation (4… Nc6 5. Nc3) 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3
Continuations
- Sicilian Defense: Four Knights Variation, Exchange Variation B45 · 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 Nf6 6. Nxc6
- Sicilian Defense: Four Knights Variation, Cobra Variation B45 · 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 Nf6 6. Ndb5 Bc5
- Sicilian Defense: Four Knights Variation, Sveshnikov Transfer B45 · 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 Nf6 6. Ndb5 d6
- Sicilian Defense: Four Knights Variation, American Attack B45 · 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 Nf6 6. Ndb5 Bb4 7. Nd6+
More Sicilian Defense lines (all)
- Sicilian Defense (1. e4 c5) B20
- Sicilian Defense: Amazon Attack B20
- Sicilian Defense: Big Clamp Formation 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
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.