[Event "Interzonal-06"]
[Site "Amsterdam"]
[Date "1964.05.21"]
[Round "2"]
[White "Porat, Yosef"]
[Black "Ivkov, Borislav"]
[Result "1/2-1/2"]

1. Nf3 Nf6 2. b3 d6 3. d4 g6 4. Bb2 Bg7 5. g3 O-O 6. Bg2 Nbd7 7. O-O e5 8. dxe5 Ng4 9. c4 dxe5 10. h3 Nh6 11. e4 Re8 12. Nc3 c6 13. Qd2 f6 14. Rad1 Nf7 15. Na4 Qe7 16. Qc1 Bf8 17. Ne1 Nb6 18. Nc3 Ng5 19. h4 Ne6 20. Nc2 Qg7 21. Ba3 Bxa3 22. Qxa3 Qe7 23. Qxe7 Rxe7 24. Rd6 Kf7 25. f4 exf4 26. gxf4 Rd7 27. Rxd7+ Bxd7 28. Kh2 a5 29. e5 fxe5 30. fxe5+ Ke7 31. Ne4 Rf8 32. Rxf8 Kxf8 33. Bh3 Nf4 34. Bxd7 Nxd7 35. Nd6 b6 36. Nd4 Nxe5 37. Nc8 c5 38. Nb5 Nd7 39. Nc3 Ke8 40. Kg3 Nd3 41. Na4 Nc1 42. Ncxb6 Nxb6 43. Nxb6 Ke7 44. Kf4 Nxa2 45. Na4 Kd6 46. Kg5 Nc1 47. Kh6 Nxb3 48. Kxh7 Nd2 49. Kxg6 Nxc4 50. h5 Ne5+ 51. Kf5 Nf7 52. Kg6 1/2-1/2