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

(Redirected from Chess/King's Knight Opening)

Open Game
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Position in Forsyth-Edwards Notation (FEN)
Moves: 1. e4 e5 2. Nf3
Responses:

## 2. Nf3 - Open Game

Black's valuable center pawn is threatened with capture, but White's pawn remains safe.

The question for Black at this point is whether to challenge the White pawn on e4 or support the Black one on e5.

### Supporting the Black pawn

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2...Nc6   (King's Knight, main line)

2...Nc6 is the natural move, combining defence of the pawn with control of the d4 square and avoiding committing another pawn for now.

2. Nf3 is 10 times more popular than everything else combined, and in turn the reply 2...Nc6 is about 5 times more popular than everything else combined.

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2...d6   (Philidor)

2...d6, Philidor's Defence, is the other safe option to defend the pawn.

It restricts the f8 bishop to the e7 square, and grants White an advantage in territory, but it builds a fortress that cannot be easily battered down. This is generally considered an inferior way to defend the e5 pawn because white can easily push for advantage here, and white gets a 58% score here, with 41% wins opposed to black's 25%. This is especially the case if black makes a c7-c5 push to kick a potential knight on d4, greatly weakening the d6 pawn.

An alternative (older) way to play this is to follow up with 3...f5, but more recent analyses have proven this line to be completely losing for black

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2...f6?   (Damiano)

Note that 2...f6? is a bad move.

It has a name, Damiano's Defence, but poor Damiano never wanted his name associated with it because it doesn't work – White captures the pawn anyway, and capturing the knight back with the pawn just loses the game.

### Challenging the White pawn

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2...Nf6   (Petrov)

2...Nf6 is the Petrov Defence.

Black wants the same things that White wants, but once again White will be back in a symmetrical position with the advantage of moving first. This opening is known to be notoriously drawish due to the resultant symmetric positions.

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2...f5   (Latvian Gambit)

2...f5 is the Latvian Gambit.

This iconic counter-thrust divides opinion like very few other openings.

Has Black lured White into a minefield of tricks and traps leading to an inevitable violent death?

Or has Black given away a pawn for nothing?

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2...d5   (Elephant Gambit)

2...d5 is the Elephant Gambit.

It's along the same lines as the Latvian, but less complex – White needs to do less memorising to reach a good position.

## Statistics

Estimated next move popularity

Nc6 83.5%, Nf6 11%, d6 4%, f5 0.5%, other less than 0.5%.

## Theory table

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

1. e4 e5 2. Nf3

2 3 4 5
Ruy Lopez ...
Nc6
Bb5
a6
Ba4
Nf6
O-O
Be7
=
Petrov's Defence ...
Nf6
Nxe5
d6
Nf3
Nxe4
d4
d5
=
Philidor Defence ...
d6
d4
exd4
Nxd4
Nf6
Nc3
Be7
+=
Latvian Gambit ...
f5
Nxe5
Qf6
d4
d6
Nc4
fxe4
+/-
Elephant Gambit ...
d5
exd5
Bd6
d4
e4
Ne5
Nf6
+=
Câmara Defence ...
Qe7
Bc4
d6
O-O
g6
d4
Bg7
+=
Greco Defence ...
Qf6
Bc4
Qg6
Nc3 +/-
Damiano Defence ...
f6
Nxe5
Qe7
Nf3
Qxe4
Be2 +/-