The McDonnell Gambit is a chess opening gambit in the King's Gambit, Classical Variation that begins with the moves: 1. e4 e52. f4 exf43. Nf3 g54. Bc4 g45. Nc3 or alternatively via the Quaade Gambit: 4. Nc3 g45. Bc4 The opening is named after Alexander McDonnell, a 19th-century Irish chess master, who successfully introduced it in his third match with Louis-Charles Mahé de La Bourdonnais. The aim is to gain a significant lead in development (knight, bishop, and queen) for the sacrificed knight, followed by a kingside attack.