[Event "Interzonal-09b"]
[Site "Petropolis"]
[Date "1973.07.25"]
[Round "2"]
[White "Hug, Werner"]
[Black "Ivkov, Borislav"]
[Result "1/2-1/2"]

1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Bxc6 dxc6 5. Nc3 f6 6. d4 exd4 7. Nxd4 c5 8. Nde2 Qxd1+ 9. Nxd1 Bd7 10. Bf4 O-O-O 11. Ne3 Bc6 12. f3 Ne7 13. Rd1 Rxd1+ 14. Kxd1 g6 15. Kc1 Bg7 16. h4 Re8 17. Rd1 1/2-1/2