Semi-Slav Defense: Stonewall Defense

The Semi-Slav Defense: Stonewall Defense is a chess opening classified under ECO code D45 in the Closed & Semi-Closed Games family, arising from 1.d4 d5, including the Queen's Gambit, Slav Defense, and related systems. It is reached after 6 moves: 1. d4 d5 2. Nf3 Nf6 3. c4 c6 4. Nc3 e6 5. e3 Ne4 6. Bd3 f5. The resulting position leaves white to move.