[Event "1973 Canadian Open"]  [Site "Ottawa"]  [White "Kevin Spraggett"]  [Black "Bruce Amos"]  [Result "1-0"]  [ECO "C05"]  [Annotator "ATH"]  [PlyCount "67"]  [EventDate "1973.07.28"]  [EventType "swiss"]  [EventRounds "11"]  [EventCountry "CAN"]  [SourceTitle "Canbase"]  [SourceDate "2015.08.19"]  [SourceVersion "1"]  [SourceVersionDate "2015.08.19"]  [SourceQuality "1"]   1. e4 e6 2. d4 d5 3. Nd2 Nf6 4. e5 Nfd7 5. f4 (5. Bd3 $14) 5... c5 6. c3 Nc6 7.  Ndf3 Qa5 $6 (7... Qb6 $1 8. g3 Be7 9. Ne2 O-O 10. Bh3 a5 $11) 8. Kf2 (8. dxc5  $1 Qxc5 9. Bd3 f6 10. Qe2 $14 {Michiels-Rasmussen, Hinnerup 1979}) 8... b5 9.  Bd3 $6 (9. a3 c4 $11) 9... b4 10. Ne2 Nb6 $6 (10... Be7 $1 $15) 11. Bd2 Na4 $2  (11... Nc4 $1 $11) 12. Rb1 (12. cxb4 $1 Nxb4 13. Bxb4 cxb4 14. Qd2 $16) 12...  Bd7 13. g4 $6 (13. f5 $1 exf5 14. Nf4 $16) 13... Rb8 14. cxb4 Nxb4 15. Bc2 (15.  Kg2 $5) 15... Qa6 $2 (15... cxd4 16. Nexd4 Qa6 17. Bxa4 Bxa4 18. Qe2 Be7 $11)  16. b3 Nb6 17. Bxb4 cxb4 18. Ra1 (18. f5 $1 $16) 18... Be7 (18... h5 $1 19. Bd3  Bb5 20. Bxb5+ Qxb5 21. g5 $16) 19. Qd2 (19. f5 $1 $16) 19... Rc8 (19... Bb5 20.  Ng3 $16) 20. f5 f6 $2 (20... Bb5 21. Nf4 $16) 21. Bd3 Bb5 (21... Nc4 $5 22.  bxc4 dxc4 23. Be4 c3 24. Qe3 $18) 22. Bxb5+ Qxb5 23. exf6 Bxf6 24. Nf4 exf5 (  24... O-O 25. Nxe6 $18 {puts up more resistance}) 25. Rhe1+ (25. g5 $18 {  is even stronger}) 25... Kf7 26. g5 Bd8 27. Re5 $2 (27. Ne5+ Kg8 28. h4 $18)  27... g6 $2 (27... Rf8 28. Rxf5+ Kg8 29. Rxf8+ Kxf8 30. Rc1 $16) 28. Rae1 Rf8  29. Ne6 (29. Re6 $1 Nd7 30. Rd6 $18 {is the quick method}) 29... Re8 $2 ({  Black can prolong the game by giving up the exchange with} 29... Be7 {but why?}  ) 30. Qe3 Qc6 (30... Qd7 {is a pointless improvement}) 31. Nxd8+ Rcxd8 32. Re7+  Kf8 (32... Kg8 {postpones checkmate but, again, why?}) 33. Qe5 Qc2+ 34. Kg1 1-0