Grob's Attack is an irregular chess opening defined by the move 1.g4. ECO code: A00.

History

The opening is named after Henri Grob (1904–1974), a Swiss International Master who analysed it extensively and played hundreds of correspondence games with it. Grob himself referred to it as the Spike Opening in his newspaper column. Earlier names include Ahlhausen's Opening (after Carl Ahlhausen of Berlin, 1835–1892) and the Genoa or San Pier d'Arena Opening, a name given by Savielly Tartakower after the location where he first employed it.

Main Lines & Variations

Black's two main responses are 1...d5 and 1...e5, both seizing central space.

After 1...d5, White typically plays 2.Bg2, and the game may continue:

• 2...Bxg4 – Capturing the pawn immediately. White plays 3.c4 (the Fritz Gambit) seeking compensation through rapid queenside development.

• 2...c6 3.g5 – The Spike Attack, maintaining the advanced pawn and cramping Black's kingside.

After 1...d5 2.Bg2 Bxg4 3.c4 d4, the Romford Counter-Gambit arises, where Black advances the d-pawn seeking active play.

The Keene Defence runs 1.g4 d5 2.h3 e5 3.Bg2 c6, building a solid centre against White's flank approach.

Key Positions

After 1.g4 d5 – Black occupies the centre; White will fianchetto with Bg2.

Strategic Themes & Plans

White's three principal plans are: supporting the g4-pawn with h3; pressuring d5 or the h1–a8 diagonal via the fianchettoed bishop; and launching a kingside pawn storm with h4–h5. International Master John Watson has observed that "as far as I can tell, 1.g4 is competitive with 1.h4 for the honour of being White's worst first move." Michael Basman notably defeated Grandmaster John Nunn with the Grob at Oxford in 1978. At the 2018 TCEC Season 12 superfinal, both Stockfish and Komodo evaluated the position after 1.g4 as providing a clear advantage for Black.