[Event "IBM"]
[Site "Amsterdam"]
[Date "1971.07.13"]
[Round "1"]
[White "Langeweg, Kick"]
[Black "Portisch, Lajos"]
[Result "1-0"]

1. Nf3 Nf6 2. c4 g6 3. d4 Bg7 4. Nc3 d5 5. cxd5 Nxd5 6. Bd2 O-O 7. Rc1 Nb6 8. Bg5 h6 9. Bh4 g5 10. Bg3 c5 11. e3 cxd4 12. Nxd4 Nc6 13. Nxc6 Qxd1+ 14. Nxd1 bxc6 15. h4 g4 16. e4 Be6 17. Ba6 Rad8 18. b3 Rd4 19. f3 gxf3 20. gxf3 Bc8 21. Be2 Bb7 22. Rg1 Kh8 23. Ne3 e6 24. Ng4 f5 25. Ne5 Kh7 26. Ng6 Rg8 27. h5 fxe4 28. Bf2 Rd7 29. fxe4 Bb2 30. Rc2 Ba3 31. Bc5 Bxc5 32. Rxc5 Rd4 33. Ra5 a6 34. Re5 Bc8 35. Rf1 Rd6 36. Ra5 Kg7 37. Bxa6 Rd4 38. Rf4 Re8 39. Be2 Nd7 40. Ra7 e5 41. Rg4 Kf6 42. Bc4 Rxc4 43. bxc4 Nc5 44. Rg2 Nxe4 45. Nh4 Ng5 46. Rf2+ Ke6 47. Nf5 Rd8 48. Ng7+ Kd6 49. Rd2+ 1-0