[Event "Petropolis Interzonal"]
[Site "Petropolis"]
[Date "1973.??.??"]
[Round "13"]
[White "Portisch, Lajos"]
[Black "Biyiasas, Peter"]
[Result "1-0"]
[WhiteElo "2645"]
[BlackElo "2395"]
[ECO "A42"]

1.d4 g6 2.c4 d6 3.Nc3 Bg7 4.e4 e5 5.d5 Qe7 6.Be2 Bh6 7.Bxh6 Nxh6 8.Qd2 Ng4
9.h3 Nf6 10.Nf3 O-O 11.Nh2 Nbd7 12.Qe3 a5 13.g4 Nc5 14.O-O-O Ne8 15.Rdf1 Ng7
16.Bd1 Bd7 17.Bc2 Rae8 18.f4 f5 19.fxe5 Qxe5 20.Nf3 f4 21.Nxe5 fxe3 22.Nxd7 Nxd7
23.Ba4 Re7 24.Bxd7 Rxd7 25.Rxf8+ Kxf8 26.Rf1+ Rf7 27.Rxf7+ Kxf7 28.Kd1 Kf6
29.Ke2 Kg5 30.Kxe3 Kh4 31.Nb5 Kxh3 32.Nxc7 Kxg4 33.c5 Kg5 34.cxd6 Kf6 35.e5+ Kf7
36.Kf4 Nf5 37.e6+ Kf8 38.e7+  1-0

