Chess puzzle (Crushing)
Opening: Queens_Gambit_Declined, Queens_Gambit_Declined_Marshall_Defense
Moves: 1. d4 d5 2. c4 Nf6 3. cxd5 Nxd5 4. e4 Nb6 5. Nf3 e6 6. Nc3 Bb4 7. Qa4+ *
Position (FEN): rnbqk2r/ppp2ppp/1n2p3/8/Qb1PP3/2N2N2/PP3PPP/R1B1KB1R b KQkq - 3 7
Black to move.
Themes: Pin Opening  
Puzzle rating: 1591
Best move: Nxa4