Bird Gambit

The Bird Gambit is White's answer to the Exchange Variation of the Philidor Defense. White does not recapture on d4 with 4. Nxd4. Instead, 4. c3 offers the c-pawn in the manner of the Göring and Danish Gambits. If Black captures, White gains time and open lines for development, and the pawn on d6 already restricts Black's dark-squared bishop. If Black declines, the d4-pawn is undermined and White hopes to rebuild a broad center with cxd4.

Accepting with 4...dxc3 is by far the most common reply. White scores well after it in practice, even though engines rate the gambit as roughly balanced. The most popular alternative is 4...Nf6, which ignores the offer and counterattacks the e4-pawn. This reply has given Black better practical results than taking the pawn. Engines also consider 4...Qe7 playable, pinning the e-pawn, and 4...Nc6 is occasionally seen. The gambit sees modest use in online play and is mainly a way to steer the Philidor toward open, tactical positions rather than the cramped structures of the main lines.