[Event "Siegen Olympiad"] [Site "?"] [Round "0"] [White "Spassky"] [Black "Kostro"] [Result "1-0"] [ECO "D15"] [Opening "Slav: 4.Nc3"] 1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 e6 5. Bg5 h6 6. Bh4 dxc4 7. e4 g5 8. Bg3 b5 9. Be2 Bb7 10. O-O Nbd7 11. d5 cxd5 12. exd5 Qb6 13. dxe6 fxe6 14. Nd4 Bc5 15. Ndxb5 O-O 16. Bf3 Bxf3 17. Qxf3 Rac8 18. Rad1 Qc6 19. Qe2 Nd5 {White's fo rces do not seem well-placed to attack the enemy king, in spite of the weaknesses on the kingside. But the pawn at e6 is very weak, and White can use the idea of interference to get at it.} 20. Nd6 Bxd6 21. Qxe6+ {Mission accompl ished! Not only is the attack under way, but White will even recover the material investment at d6.} 21... Kg7 22. Bxd6 1-0