[Event "Interzonal-04"]
[Site "Portoroz"]
[Date "1958.09.10"]
[Round "21"]
[White "De Greif, Boris"]
[Black "Olafsson, Fridrik"]
[Result "0-1"]

1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 c5 5. Bd3 O-O 6. Nf3 b6 7. O-O Bb7 8. Bd2 d6 9. a3 Bxc3 10. Bxc3 Nbd7 11. Qe2 Qc7 12. Rfd1 e5 13. dxe5 dxe5 14. Bf5 Rfe8 15. Nd2 e4 16. Bxd7 Nxd7 17. Qg4 Ne5 18. Qg3 f6 19. Nf1 Qf7 20. Bxe5 Rxe5 21. b3 Rae8 22. a4 Bc8 23. h4 h6 24. Rd6 Kh7 25. Rad1 Qh5 26. R1d2 R8e7 27. Rd8 Bg4 28. Rf8 Bd7 29. Rd8 Be6 30. Qf4 Qf7 31. Nh2 Qg6 32. Nf1 Qf7 33. Nh2 g5 34. hxg5 hxg5 35. Qg3 Qh5 36. Rf8 Kg6 37. f4 exf3 38. Nxf3 Re4 39. Rdd8 Bf7 40. Rd6 R4e6 41. Rxe6 Rxe6 42. Qc7 Kg7 43. Ra8 Rxe3 44. Qd6 Re8 45. Rxa7 g4 46. Qd7 Kg8 47. Nh4 g3 48. Nf3 Qg6 49. Qd1 Qe4 50. Rd7 Qe3+ 51. Kh1 Kg7 52. Rd8 Qh6+ 0-1