Chess puzzle (Advantage)
Opening: Semi-Slav_Defense, Semi-Slav_Defense_Other_variations
Moves: 1. d4 d5 2. c4 Nf6 3. Nc3 c6 4. Nf3 e6 5. Bf4 Bb4 6. Qb3 Bxc3+ 7. bxc3 O-O 8.
e3 dxc4 9. Bxc4 b5 10. Bd3 a5 11. a4 Nd5 12. axb5 Nxf4 13. exf4 cxb5 14. Qxb5
Ba6 15. Qxa5 Bxd3 16. Qxa8 Qc7 17. Rc1 *
Position (FEN): Qn3rk1/2q2ppp/4p3/8/3P1P2/2Pb1N2/5PPP/2R1K2R b K - 2 17
Black to move.
Themes: Defensive Move Middlegame  
Puzzle rating: 2038
Best move: Na6