Petroff Defense

The Petroff (1.e4 e5 2.Nf3 Nf6) is the original mirror reply. Instead of defending e5, Black attacks e4 - if White takes on e5, Black takes back on e4. The result is a symmetric, drawish-looking opening that's actually a serious weapon at the top level. Kramnik, Carlsen, Caruana and Karpov have all used it to neutralise 1.e4. It's the choice when you want a quiet game with Black.

Main line: Classical (3.Nxe5)

White takes the pawn. The critical move is 3...d6! - not 3...Nxe4? immediately, which loses to 4.Qe2 pinning the knight and threatening Nxc6+. After 3...d6 4.Nf3 Nxe4 5.d4 d5 6.Bd3 Bd6 7.O-O O-O, both sides are symmetric, both knights are active, and White has only a tiny edge in tempo. Modern theory suggests Black equalises with accurate play.

Variations

Three Knights (3.Nc3)

Instead of grabbing the pawn, White develops. Black can play 3...Nc6 transposing to the Four Knights Game, or 3...Bb4 (Three Knights, going for a Spanish-like structure). Less ambitious than the main line - White accepts a quiet game.

Italian-style attack (3.Bc4)

White develops the bishop and threatens nothing immediate. Black should play 3...Nxe4 with care - the line 3...Nxe4 4.Nc3 Nxc3 5.dxc3 favours White slightly because of better piece activity. More reliable is 3...Bc5 leading to an Italian Game.

Cochrane Gambit (4.Nxf7!?)

An old surprise: after 3.Nxe5 d6 4.Nxf7?! Kxf7, White sacrifices a knight for two pawns and the right to attack a king in the centre. Looks insane and probably is - but at club level it scores well because Black has to defend accurately while down a piece. If you're a Black Petroff player, you must know how to defend this.

Common traps

Don't capture on e4 too early: 1.e4 e5 2.Nf3 Nf6 3.Nxe5 Nxe4?? 4.Qe2 Nf6 5.Nc6+ wins the queen via a discovered attack. The 3...d6 move first is essential - it forces White to retreat the knight before the e4 pawn is grabbed.

Watch out for Qe2 ideas: any time White's queen sits on e2 with a knight on f3 and Black's knight in front of the king, discovered attacks become a constant threat. Always check that your king isn't on the same file as White's queen before moving a knight.

Typical plans for Black

Black's whole strategy is symmetry-into-endgame. Develop classically (knight to c6, bishop to d6 or e7, castle short), then trade pieces and head for an even endgame. The Petroff is the favourite of grandmasters who want a draw with Black against stronger opposition - and the favourite weapon of players who outwork their opponents in endgames.

If you want a low-theory, low-risk Black opening against 1.e4, the Petroff is hard to beat. The drills below cover the Classical main line and the Cochrane.