[Event "Interzonal-10a"]
[Site "Biel"]
[Date "1976.08.06"]
[Round "19"]
[White "Castro Rojas, Oscar Humberto"]
[Black "Portisch, Lajos"]
[Result "0-1"]
[WhiteElo "2380"]
[BlackElo "2625"]

1. e4 c5 2. Nf3 e6 3. c3 Nc6 4. d4 d5 5. exd5 exd5 6. Be2 Bd6 7. dxc5 Bxc5 8. b4 Be7 9. O-O Nf6 10. b5 Na5 11. Nbd2 O-O 12. c4 Bg4 13. Nd4 dxc4 14. Bb2 Bb4 15. a3 c3 16. axb4 cxb2 17. Ra4 Qxd4 18. Bxg4 Nc4 19. Nxc4 Qxc4 20. Bf5 Rad8 21. Qf3 Nd5 22. Ra3 g6 23. Bb1 Rfe8 24. g3 Qc1 25. Kg2 Re1 26. Rxe1 Qxe1 27. Qe4 Qxe4+ 28. Bxe4 Nf6 0-1