Dutch Variation, Batavo Gambit

The Batavo Gambit is a pawn offer in which White meets the Tal Gambit, 1. e4 c5 2. f4 d5, with 3. Nf3 and permits 3...dxe4. The moves are a Sicilian sequence, classified under B21. The name nonetheless belongs to the Dutch Variation of the Bird Opening, because the same position also comes from 1. f4 d5 2. Nf3 c5 3. e4 dxe4. White rejects 3. exd5 and the blocking 3. e5 and plays for development instead of material. Black's extra pawn on e4 leaves doubled e-pawns, but it hits the f3-knight and controls d3 and f3. The half-open d-file also lets Black put pressure on White's queenside and center.

White nearly always moves the attacked knight. The most common choice is 4. Ng5, which targets the e4-pawn at once. The second choice is 4. Ne5, which the engine ranks first, and it also rates the rarely seen check 4. Bb5+ highly. The retreat 4. Ng1 is an uncommon alternative. Black wins more often than White in practice, and the engine gives Black a slight advantage. This matches the view that 3. Nf3 is a dubious gambit, not a sound way to answer the Tal Gambit.