[Event "Amsterdam Interzonal"]
[Site "Amsterdam"]
[Date "1964.??.??"]
[Round "11"]
[White "Ivkov, Borislav"]
[Black "Portisch, Lajos"]
[Result "1/2-1/2"]
[WhiteElo ""]
[BlackElo ""]
[ECO "B48"]

1.e4 c5 2.Nf3 e6 3.d4 cxd4 4.Nxd4 a6 5.Nc3 Qc7 6.Bd3 Nc6 7.Be3 Nf6 8.O-O Ne5
9.h3 b5 10.f4 Nc4 11.Bxc4 Qxc4 12.e5 b4 13.Qf3 Rb8 14.exf6 bxc3 15.b3 Qc7
16.f5 Bb7 17.Bf4 e5 18.Bxe5 d6 19.Qg4 dxe5 20.fxg7 Rg8 21.gxf8=Q+ Rxf8 22.Nf3 f6
23.Rad1 Kf7 24.Qh5+ Kg7 25.Qg4+ Kf7 26.Qh5+ Kg7 27.Qg4+ Kf7  1/2-1/2

