Anglo-Grünfeld Defense

The Anglo-Grünfeld arises when Black answers 1. c4 Nf6 2. Nc3 with 2...d5, contesting the center in the manner of the Grünfeld Defense, usually followed by ...g6 and ...Bg7. Because White has not committed the d-pawn, the position differs from the Grünfeld proper. White can exchange on d5 and develop the king's bishop on the long diagonal, where it presses against the knight on d5 and Black's queenside, without building the broad pawn center Black normally targets. About two-thirds of games continue 3. cxd5, and Botvinnik chose 3. cxd5 Nxd5 4. g3 against Smyslov in their 1958 title match. The alternatives 3. d4, which returns to 1. d4 territory, and the quieter 3. e3 are far less common.

The Korchnoi Variation, 3. cxd5 Nxd5 4. Nf3 g6 5. g3 Bg7 6. Bg2 e5, has Black occupy the center with a pawn, producing a reversed Sicilian-type structure in which White's fianchettoed bishop and the half-open c-file face Black's space and active pieces. The engine considers the starting position roughly balanced, and White scores slightly better in practice.