Anglo-Indian Defense, Scandinavian Defense, Exchange Variation

The Exchange Variation of the Anglo-Indian Scandinavian arises after 1. c4 Nf6 2. Nf3 d5 3. cxd5 Nxd5. Black has given up the d-pawn for White's c-pawn and recovered the material with the knight, so the c- and d-files are half-open and White, with both central pawns still at home, has the better prospects of occupying the center. Black's compensation is free development and a structure resembling a reversed Scandinavian or Grünfeld, in which the White center can later become a target. The knight on d5, however, has no pawn support and is exposed to tempo-gaining moves.

The most frequent reply is 4. e4, which hits the knight at once and forces it to move again while White claims space. 4. Nc3 also attacks the knight and leads to the Anglo-Grünfeld Variation, where Black often aims for counterplay against the center in Grünfeld fashion. 4. d4 occupies the center first and keeps options of e4 or Nc3 later. All three are among the engine's preferred moves, and the engine assesses White as holding a slight edge. In practice White scores clearly better than Black, with 4. e4 and 4. d4 producing better results than 4. Nc3.