Anglo-Slav Opening

The Anglo-Slav Opening arises after 1. d4 c6 2. c4 d6. The first move points toward the Slav Defense, which follows only if Black plays 2...d5 here. With 2...d6, Black declines that transposition and instead adopts a low, flexible pawn chain. The d-pawn no longer contests e4 or c4, so White gains space with little resistance, and Black has to look for counterplay later rather than meeting the center head-on. The opening is classified under ECO A40.

The most frequent reply by a wide margin is 3. Nc3, which prepares e4 while developing. 3. Nf3 keeps the setup more restrained, and 3. e4 at once sets up a broad pawn center on c4, d4 and e4. Engines judge that White holds a clear advantage, although in Lichess games the results are close to even and decisive outcomes heavily outnumber draws. The line appears regularly in online play without ranking among the main defenses to 1. d4.