There aren't many clubs who have amongst their ranks players who have beaten a Polgar. In Jimmy Simpson we have.

Now, admittedly she was only 12 at the time, but it was only a mere 2 years later when she famously played out the 'Sack of Rome' when she stunned the chess world with a score of 8.5 out of 9, winning the tournament, which included several strong Grandmasters. She achieved an ELO rating of 2928. This is by far the strongest tournament result by any woman ever!

Simpson,Jim - Polgar,Sofia [A46]
Australian Open Adelaide, 1986

1.d4 Nf6 2.Nf3 c5 3.e3 cxd4 4.exd4 g6 5.Bd3 Bg7 6.0-0 0-0 7.Re1 Nc6 8.c3 d6 9.Bg5 h6 10.Bxf6 Bxf6 11.Nbd2 e5 12.dxe5 dxe5 13.Qc2 Qc7 14.Rad1 Be6 15.Be4 Ne7 16.Nf1 Bg7 17.Qa4 f5 18.Bc2 Nd5? 19.Bb3 Rad8 20.Ne3 Qf7? [20...Nf4 ]

21.Nxd5 Bxd5 22.Qa5 b5?? [22...Bxb3 23.Rxd8 b6 24.Rxf8+ Bxf8 25.Qxe5 Bxa2+- ]

23.Nxe5 Qe6 24.Nd3? [24.Rxd5 Rxd5 25.Nd3 Qd7 26.Nf4 Kh7 27.Nxd5 ]

24...Qf6 25.Qxb5 Bxb3 26.Qxb3+ Kh7 27.Nf4 Rfe8 28.Rxe8 Rxe8 29.g3 Qe5 30.Qf7! g5 31.Qg6+ Kg8 32.Nh5 Rb8 33.Nxg7 Qxg7 34.Qe6+ 1-0