Wing Gambit

The Wing Gambit, 2. b4, offers White's b-pawn to pull the c-pawn away from its watch over d4. If Black accepts, White hopes to follow with d4 and build a broad center, with open lines on the queenside for the pieces. The most frequent continuation is 2...cxb4 3. a3, the Marshall Variation, which aims to regain time by developing the knight via a3 or c3. Here 3...bxa3 is the Carlsbad Variation, while 3...d5 4. exd5 Qxd5 5. Bb2 is the Marienbad. Other third moves are 3. Bb2, the Abrahams Variation, and 3. c4, the Santasiere. Black may also decline: 2...e6 and 2...b6 are both seen, and 2...d5 hits e4 at once. White can delay the idea with 2. Nf3 d6 3. b4, the Deferred Variation.

Theory regards the gambit as dubious, and the engine gives Black a slight edge. It has rarely appeared in grandmaster play since the era of Frank Marshall and Rudolph Spielmann, but it remains common among amateurs, and in online games White's results are roughly level with Black's.