# Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nf6

< Chess Opening Theory‎ | 1. e4‎ | 1...e5‎ | 2. Nf3(Redirected from Chess/Petroff Defence)
Petrov's Defence
 a b c d e f g h 8 8 7 7 6 6 5 5 4 4 3 3 2 2 1 1 a b c d e f g h
Position in Forsyth-Edwards Notation (FEN)

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# Petrov's Defence

### 2...Nf6

Black chose to play the Petrov's Defense. This defense is well known to be drawish and boring, especially due to the symmetrical position. However, some lines can get quite sharp and dangerous and many continuations are possible for White.

• 3. Nxe5 is the main line (or Classical Variation). In this line, it's not advised for Black to take White's pawn before having chased the knight. There is a famous trap : 3...Nxe4? 4. Qe2 Nd6?? (or 4...Nf6??) 5. Nc6+ and Black's queen is lost. There are a few lines that are quite dangerous in the Classical Variation, especially the Cochrane Gambit, which goes 3...d6 4. Nxf7, sacrificing a knight for two pawns and an exposed king. Rarely do games in the Cochrane Gambit end in a draw, especially due to the attacking opportunities and aggression offered by the position as white tries to gain a pawn back (so 3 pawns for a knight is material equality), while black tries to maintain its advantage of a pawn.
• With 3. Nc3, Black can easily transpose into the Four Knights Game with 3...Nc6. This option is sound when White wants to avoid the sharp lines of Petrov's Defence. However, black can avoid the four knights game transposition with 3...Bb4, also pressuring the knight on c3 and making the game a little more active than it would be with the slow maneuvering of the four knights game.
• 3. d4 is the Steinitz Variation. Both players will usually plant their knights in advanced positions. Exchanges often occur in this line to avoid having too powerful an enemy knight in front of the king. This is a rather sharp variation of the Petrov's Defense.
• 3. Bc4 usually transposes into the Two Knights Defence (a variation of the Italian Game) but can continue in its own line.
• 3. d3 is, according to statistics, a much more effective move than it looks, though it's rarely played. White builds a strong fortress and Black is now forced to abandon the Petrov's lines and to defend his pawn.

## Theory table

For explanation of theory tables see theory table and for notation see algebraic notation.

1. e4 e5 2. Nf3 Nf6

3 4 5 6 7 8 9 10 11 12 13 14 15
Classical Variation Nxe5
d6
Nf3
Nxe4
d4
d5
Bd3
Nc6
0-0
Be7
c4
Nb4
Be2
0-0
Nc3
Bf5
a3
Nxc3
bxc3
Nc6
Re1
Re8
cxd5
Qxd5
Bf4
Rac8
=
Steinitz Variation d4
Nxe4
Bd3
d5
Nxe5
Nd7
Nxd7
Bxd7
0-0
Bd6
c4
c6
cxd5
cxd5
Nc3
Nxc3
bxc3
0-0
Qh5
g6
Qxd5
Qc7
=
Two Knights Defence Bc4
Nc6
=
Four Knights Game Nc3
Nc6
=
d3
Nc6
=