(1) Polugaevsky,L (2620) - Pfleger,H (2530) [D34]
Buenos Aires ol (Men) Buenos Aires (9), 1978

1.c4 Nf6 2.Nf3 e6 3.g3 d5 4.Bg2 c5 5.cxd5 exd5 6.d4 Nc6 7.0-0 Be7 8.Nc3 0-0 9.Bg5 c4 10.Ne5 Be6 11.Nxc6
[ Three years earlier Pfleger had beaten "Polu" in the same line. That game continued 11.e3 Nd7= 12.Bxe7 Nxe7 13.b3 Nxe5 14.dxe5 Qa5 15.Qe1 Rfd8 16.bxc4 dxc4 17.f4 Rd3 18.Ne4 Qa3 19.Ng5 Rxe3 20.Qb1 Bf5 21.Qxb7 Rf8 22.Rae1 Rxe1 23.Rxe1 c3 24.Qf3 Rc8 25.g4 Qc5+ 26.Kh1 c2 27.Rc1 Bxg4 28.Qb3 Qc4 29.Ne4 Qe2 30.Nc3 Rxc3 0-1 Polugaevsky,L-Pfleger,H/Montilla Moriles 1975/EXT 2001 (30)]

11...bxc6 12.b3 Qa5 13.Na4 Rfd8 14.e3!
[ 14.Qc2 Rac8 15.Bxf6 Bxf6 16.Nc5 Bxd4 17.Nb7 Qb6 18.Nxd8 Rxd8 19.bxc4 Bxa1 20.cxd5 is better for Black]

14...c5 15.Bxf6 gxf6 16.dxc5 Bxc5 17.Qh5 Rac8
Polugaevsky had prepared all of this carefully and actually used it again successfully in the same tournament against the Canadian Lawrence Day.

18.Rfd1 Bf8 19.Rac1 Qb4 20.Bxd5?
[ 20.Nc3! cxb3 21.Nxd5 Rxd5 22.Bxd5 Rxc1 23.Rxc1 b2! ( 23...Qb5? 24.e4 bxa2 25.Ra1+- ) 24.Rb1 Qc5 25.e4 Qc1+ 26.Qd1 Ba3 27.Bxe6 fxe6 28.Kg2 with the idea Qd3, f4, Kh3+/= [Polugaevsky]]

20...Rxd5! 21.Rxd5 cxb3 22.Rxc8 Bxc8 23.axb3?
[ 23.Qd1 Qxa4 24.axb3 Qc6 25.Rd8 f5 -/+ would offer more resistance.]

23...Bg4! 24.Qh4
[ or 24.Rg5+ fxg5 25.Qxg5+ Bg7 26.Qd8+ Qf8 and Black is winning.]

24...Qe1+ 25.Kg2 Be2 26.g4 Qf1+ 27.Kg3 Qg1+ 28.Kf4 Qg2 29.Qxf6 Qxf2+ 30.Ke5 Qxe3+ 31.Kf5 Qf3+ 32.Kg5 Qe3+ 33.Kf5 Bd3+ 34.Rxd3 Qxd3+ 35.Kg5 Qe3+ 36.Kh5 Be7 0-1