[Event "Candidates' Tournament"] [Site "?"] [Round "0"] [White "Petrosian"] [Black "Korchnoi"] [Result "1-0"] [ECO "A31"] [Opening "English: Symmetrical, Two Knights"] 1. c4 c5 2. Nf3 Nf6 3. d4 cxd4 4. Nxd4 g6 5. Nc3 d5 6. Bg5 dxc4 7. e3 Qa5 { This early queen sortie gives White the initiative. Better was to develop normally with 7...Bg7. 7...Bg7 8.Bxc4 O-O 9.O-O a6 10.Qe2 b5 11.Bb3 Bb7 12. Rfd1 Qa5 13.e4 when White's centralized pieces give him the edge.} 8. Bxf6 { A strong move which doubles the Black f-pawns and secures the White knight on d4.} 8... exf6 9. Bxc4 Bb4 {9...Bg7 10.O-O O-O 11.Nd5 Gives the advantage to White due to, his well centralized minor pieces.} 10. Rc1 a6 { Black doesn't have time for this luxury. Better was castling.} 11. O-O Nd7 { White stands much better due to, Black's backward development.} 12. a3 { White also had the more aggresive 12. Nd5. 12.Nd5 Bd6 13.b4 Bxb4 14.Nb3 Wins material for White as Black has no way of answering both threats or 15 Nxb4 and Nc7+.} 12... Be7 {12...Bxc3 13.Rxc3 would also leave White standing better. Due to, White's better development and better pawn structure.} 13. b4 Qe5 { 13...Qxa3 14.Nd5 when White is threatening 15. Nc7+ or 15. Ra1.} 14. f4 { Black would go down quickly after 14...Qxe3+ 15. Kh1 due to the open king file} 14... Qb8 15. Bxf7+ {With all of Black's pieces on the back two ranks, White is able to start a winning attack.} 15... Kxf7 16. Qb3+ Ke8 {16...Kg7 17. Ne6+ Kh6 18.Rf3 g5 19.f5 when the Black king would find himself in a mating net.} 17. Nd5 {Although, technically White is down a piece for a pawn, he has a winning position. This is due to, Black's backward development.} 17... Bd6 18. Ne6 {White's pieces quickly move into the disorganized Black camp.} 18... b5 19. Ndc7+ Ke7 20. Nd4 {A perfect example of the saying "when you see a good move look again, you may see a better one". White is in no hurry to gain back material with 20. Nxa8 since the Black rook isn't going anywhere.} 20... Kf8 21. Nxa8 { Black resigned as 21...Qxa8 22. Qe6 Qb8 23 Nc6 Qc7 24 Ne7 would be hopeless.} 21... Qxa8 22. h4 1-0