Chess Opening Theory/1. e4/1...e5/2. Nf3/2...d6/3. d4

Philidor 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)
Moves: 1. e4 e5 2. Nf3 d6 3. d4

Philidor Defence

Black has now to deal with the dxe5 threat, but they have to be very careful as there are many traps here!

3...Bg4 is not a good idea. After 4. dxe5 Bxf3 5. Qxf3 (5. gxf3 dxe5 6. Qxd8+ Kxd8 is also good) dxe5 6. Bc4, White has a strong initiative.
3...exd4 is strange as Black gives up the center they tried to strengthen, but remains playable. In fact, it is likely the best line (leading to an equal position more easily). It is the most popular according to chessgames.com, with 1,328 games compared to 485 games with 3...Nf6.
3...Nc6 leaves Black in a little trouble after 4. Bb5.
3...Nd7, the Hanham Variation, is a path filled with traps after 4. Bc4, but may be playable if Black is careful enough.
3...f5, the Philidor counter-Gambit which is quite risky but may lead to victory, but usually leads to a clear advantage for white.
3...Nf6, the improved Hanham Variation. This is rather risky because of 4. dxe5!, where 4...dxe5 would lead to 5. Qxd8+, where Black loses castling rights.

Another option would be:

3...f6 However, this weakens the kingside and transposes to the Damiano defense (where white does not sacrifice his knight in the Damiano Defense, but instead plays d4. This is not a good idea.)

Theory table

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

1. e4 e5 2. Nf3 d6 3. d4

3
Exchange Variation d4
exd4
=
Improved Hanham Variation ...
Nf6
=
Hanham Variation ...
Nd7
+/=
Philidor Counter-Gambit ...
f5
+/=
...
Nc6
+/=
...
Bg4
+/-
...
f6
+/-

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