Clam Variation, Radisch Gambit

The Radisch Gambit arises when Black answers the Clam Variation's 3. f4, an early f-pawn thrust in the spirit of the Vienna Gambit built on the modest 2. d3, with 3...Bc5. Black does not defend e5. The bishop goes to the g1–a7 diagonal, aiming at White's kingside, and the pawn is left to be taken. Capturing with 4. fxe5 is the most common reply. It scores well for White, and the engine rates White clearly better. The main alternatives are 4. Nf3 and the space-gaining 4. f5, which has done better for Black in practice.