[Event "Interzonal-11a"]
[Site "Riga"]
[Date "1979.09.14"]
[Round "7"]
[White "Trois, Francisco R Torres"]
[Black "Gruenfeld, Yehuda"]
[Result "1/2-1/2"]
[WhiteElo "2415"]
[BlackElo "2430"]

1. Nf3 Nf6 2. c4 e6 3. b3 b6 4. g3 Bb7 5. Bg2 Be7 6. O-O O-O 7. Bb2 c5 8. e3 d5 9. Qe2 Nc6 10. Rd1 dxc4 11. bxc4 Qc7 12. Nc3 a6 13. Rab1 Rab8 14. d3 Rfd8 15. Ba1 Na7 16. e4 Ne8 17. e5 b5 18. cxb5 Nxb5 19. Ne4 Bd5 20. Rbc1 Qb6 21. Qe3 Rbc8 22. Qf4 h6 23. a4 Na7 24. Nfd2 Nc6 25. Nc4 Bxc4 26. Rxc4 Nd4 27. Bxd4 Rxd4 28. Rxd4 cxd4 29. Rc1 Rb8 30. Qd2 Bb4 31. Qc2 Bc3 32. Nxc3 Rc8 33. Qb1 Qxb1 34. Rxb1 dxc3 35. Rc1 Rc5 36. d4 Rc4 37. Bf1 Rxd4 38. Rxc3 Rxa4 39. Rc8 Kf8 40. Ra8 Ra5 41. f4 g5 42. Rxa6 Rxa6 1/2-1/2