Queen's Gambit Declined: Orthodox Defense, Classical Variation

The Queen's Gambit Declined: Orthodox Defense, Classical Variation is a chess opening classified under ECO code D68 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 13 moves: 1. d4 d5 2. c4 e6 3. Nf3 Nf6 4. Nc3 Be7 5. Bg5 O-O 6. e3 Nbd7 7. Rc1 c6 8. Bd3 dxc4 9. Bxc4 Nd5 10. Bxe7 Qxe7 11. O-O Nxc3 12. Rxc3 e5 13. Qb1. The resulting position leaves black to move.