Chess puzzle (Advantage)
Opening: Queens_Gambit_Declined, Queens_Gambit_Declined_Marshall_Defense
Moves: 1. d4 d5 2. c4 Nf6 3. Bg5 dxc4 4. e3 Be6 5. Nd2 h6 6. Bxf6 exf6 7. Nxc4 Bb4+ 8.
Nd2 Nc6 9. a3 Ba5 10. b4 Bb6 11. Ngf3 a5 12. bxa5 Bxa5 13. Bd3 O-O 14. O-O Bc3
15. Rb1 b6 16. Rc1 Rxa3 *
Position (FEN): 3q1rk1/2p2pp1/1pn1bp1p/8/3P4/r1bBPN2/3N1PPP/2RQ1RK1 w - - 0 17
White to move.
Themes:  Middlegame  
Puzzle rating: 1991
Best move: Nb1