Queen's Gambit Declined: Austrian Defense, Gusev Countergambit

The Queen's Gambit Declined: Austrian Defense, Gusev Countergambit is a chess opening classified under ECO code D06 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 3 moves: 1. d4 d5 2. c4 c5 3. cxd5 Nf6. The resulting position leaves white to move.