Chess opening · ECO C40
King's Knight Opening
After 1.e4 e5, the move 2.Nf3 develops a piece, prepares castling, and attacks the e5 pawn. Black's second move decides the whole character of the game. Defending with a knight leads to the Ruy Lopez, Italian and Scotch families, defending with a pawn leads to the Philidor, and counterattacking leads to the Petrov or one of the gambits.
- Rank by weighted share
- #3 of 159
Key moves
1. e4 e5 2. Nf3
- 2. Nf3The knight hits e5 right away, so Black must respond to a direct threat on move two. It also clears g1 and puts White one step closer to castling short.
Guarding e5 with a piece or a pawn
The move 2...Nc6 defends while developing and keeps both of Black's bishops free. The Philidor's 2...d6 guards e5 just as well but shuts in the f8 bishop behind the d6 pawn.
Petrov's Defense, 2...Nf6, does not defend at all. It attacks e4 in return and dares White to take on e5 first.
Why 2...f6 backfires
Guarding e5 with the f-pawn weakens the diagonal from h5 to e8. After 3.Nxe5 fxe5 4.Qh5+ g6 5.Qxe5+, the queen checks the king and attacks the h8 rook at once, and White gets back much more than the knight.
Into a Ruy Lopez
2... Nc6 3. Bb5 a6 4. Ba4 Nf6 5. O-O
The bishop on b5 pressures the c6 knight that guards e5. Black asks the bishop where it is going with ...a6, then develops the other knight to hit e4 while White castles.
Top replies by rating
Nc6 leads in every band, and its lead widens as ratings go up. At 2000 and up, Nf6 moves ahead of d6 into second place.
Questions
Can Black ignore the attack on e5?
Yes, by hitting back. The Elephant Gambit with 2...d5 and the Latvian Gambit with 2...f5 both leave e5 hanging in exchange for open lines and quick play against White's center.
Related openings
Try it on the board. The first coached game and three analyses are free.