[Event "Interzonal-09b"]
[Site "Petropolis"]
[Date "1973.07.28"]
[Round "4"]
[White "Polugaevsky, Lev"]
[Black "Biyiasas, Peter"]
[Result "1-0"]

1. d4 Nf6 2. c4 e6 3. Nf3 d5 4. Nc3 c6 5. e3 Nbd7 6. Bd3 dxc4 7. Bxc4 b5 8. Bd3 a6 9. e4
c5 10. d5 e5 11. b3 Bd6 12. O-O O-O 13. Re1 Rb8 14. Bf1 Re8 15. a4 b4 16. Nb1 Nb6 17. Nbd2
Re7 18. Bb2 Ne8 19. Rc1 f6 20. a5 Na8 21. Nc4 Rc7 22. Nfd2 Bd7 23. f4 Qe7 24. fxe5 fxe5
25. Nxd6 Nxd6 26. Nc4 Nxc4 27. Bxc4 1-0