Petrov's Defense: Three Knights Game
1. e4 e5 2. Nf3 Nf6 3. Nc3
The Petrov's Defense: Three Knights Game is a chess opening classified as ECO C42, reached after 1. e4 e5 2. Nf3 Nf6 3. Nc3. It is a line of the Petrov's Defense. Black is to move. 4 named lines continue from this position.
In 12.6 million rated Lichess games (blitz and slower), this position was reached 71,555 times by this move order. White won 51%, 4% were drawn and Black won 45%. The most popular continuation is 3… Nc6 (45% of games).
Engine evaluation: +0.08 (Stockfish, depth 55; best line 3… Nc6 4. d4 exd4 5. Nxd4 Bb4 6. Nxc6)
- ECO
- C42
- Moves
- 5 plies
- FEN
rnbqkb1r/pppp1ppp/5n2/4p3/4P3/2N2N2/PPPP1PPP/R1BQKB1R b KQkq - 3 3- PGN
1. e4 e5 2. Nf3 Nf6 3. Nc3
Analyse with Stockfish · Board image (SVG) · Open on Lichess
Results by rating
| Average rating | Games | White / draw / Black |
|---|---|---|
| 0-1499 | 39,354 | |
| 1500-1999 | 28,048 | |
| 2000+ | 4,153 | |
| All | 71,555 |
Most played moves
| Move | Games | White / draw / Black |
|---|---|---|
| 3… Nc6 | 32,142 (45%) | |
| 3… Bc5 | 16,918 (24%) | |
| 3… Bb4 | 9,985 (14%) | |
| 3… d6 | 5,293 (7%) | |
| 3… d5 | 3,168 (4%) | |
| 3… c6 | 1,326 (2%) | |
| 3… Bd6 | 574 (1%) | |
| 3… Ng4 | 415 (1%) |
Master games
7,286 over-the-board games are classified under this line (White 44%, draw 24%, Black 32%). The strongest:
- GM Magnus Carlsen (2847) – GM So, W. (2770) 1-0 · Magnus Carlsen Inv KO · 2021-03-20
- GM Fabiano Caruana (2792) – GM Ian Nepomniachtchi (2782) 1/2-1/2 · World Rapid 2021 · 2021-12-28
- GM Magnus Carlsen (2863) – GM Xiangzhi Bu (2705) 1-0 · FIDE Steinitz Mem Open · 2020-05-16
- GM Hikaru Nakamura (2780) – GM Fabiano Caruana (2786) 1-0 · FIDE Grand Swiss 2023 · 2023-11-04
- GM Hikaru Nakamura (2807) – GM Ian Nepomniachtchi (2742) 0-1 · Titled Tue 1st Jul Early · 2025-07-01
Search all games of the Petrov's Defense: Three Knights Game and its sub-variations
Highest-rated Lichess games
- GM Niksss2023 (2813) – ScaryIndianJunior (2818) 1-0 · 2026-09-03 · 180 + 0s
- Lifvix01 (2810) – zhuzhu415 (2677) 1-0 · 2026-09-04 · 180 + 0s
- IM shuriks91 (2804) – madcap_tr (2634) 1/2-1/2 · 2026-09-04 · 180 + 0s
Comes from
Petrov's Defense (2. Nf3 Nf6) 1. e4 e5 2. Nf3 Nf6
Continuations
- Four Knights Game: Spanish Variation, Rubinstein Variation, Henneberger Variation C48 · 1. e4 e5 2. Nf3 Nf6 3. Nc3 Nc6 4. Bb5 Nd4 5. O-O
- Four Knights Game: Spanish Variation, Rubinstein Variation (5… Qe7 6. f4) C48 · 1. e4 e5 2. Nf3 Nf6 3. Nc3 Nc6 4. Bb5 Nd4 5. Nxe5 Qe7 6. f4
- Four Knights Game: Spanish Variation, Gunsberg Counterattack C49 · 1. e4 e5 2. Nf3 Nf6 3. Nc3 Nc6 4. Bb5 Bb4 5. O-O O-O 6. Nd5 Nxd5 7. exd5 e4
- Four Knights Game: Spanish Variation, Symmetrical Variation, Tarrasch Variation C49 · 1. e4 e5 2. Nf3 Nf6 3. Nc3 Nc6 4. Bb5 Bb4 5. O-O O-O 6. d3 d6 7. Bg5 Be6
More Petrov's Defense lines (all)
- Petrov's Defense (2… Nf6 3. Nxe5) C42
- Petrov's Defense (3. Nxe5 d6) C42
- Petrov's Defense (3… d6 4. Nf3) C42
- Petrov's Defense (4. Nf3 Nxe4) C42
- Petrov's Defense: Classical Attack C42
- Petrov's Defense: Classical Attack, Berger Variation C42
- Petrov's Defense: Classical Attack, Chigorin Variation C42
- Petrov's Defense: Classical Attack, Chigorin Variation, Browne Attack C42
- Petrov's Defense: Classical Attack, Chigorin Variation, Main Line C42
- Petrov's Defense: Classical Attack, Closed Variation C42
- Petrov's Defense: Classical Attack, Jaenisch Variation C42
- Petrov's Defense: Classical Attack, Krause Variation C42
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.