Slav Defense: Quiet Variation, Schallopp Defense

The Slav Defense: Quiet Variation, Schallopp Defense is a chess opening classified under ECO code D12 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 4 moves: 1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. e3 Bf5. The resulting position leaves white to move.