Queen's Gambit Declined: Cambridge Springs Defense

The Queen's Gambit Declined: Cambridge Springs Defense is a chess opening classified under ECO code D52 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. c4 c6 3. Nf3 Nf6 4. Nc3 e6 5. Bg5 Nbd7 6. e3 Qa5. The resulting position leaves white to move.