Here, black continued with the illegal move 24…,O-O, which wasn’t noticed by both players. The game continued 25.Qxe7 Bb1 26.Rd2 Rxd2 27.Kxd2 Qd3+ 28.Ke1 Bc2 29. f4 Qxe3+ 30.Kf1 Bd3 mate
Lemmens, Paul (1333)
Swijsen, Willy (1567)
Resultaat: 0-1
Swijsen, Willy (1567)
Resultaat: 0-1
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1. e4 d5 2. exd5 Nf6 3. Nf3 Nxd5 4. d4 Bg4 5. c4 Nb4 6. Qa4+ N8c6 7. d5 b5 8. Qb3 Bf5 9. Na3 Qd6 10. dxc6 Rd8 11. Be2 Nd3+ 12. Bxd3 Bxd3 13. Bd2 b4 14. Nb5 Qxc6 15. Nfd4 Qe4+ 16. Be3 e5 17. Nxc7+ Kd7 18. Qa4+ Kxc7 19. Nb5+ Kd7 20. Qxa7+ Ke6 21. Qb6+ Kd7 22. Qc7+ Ke8 23. O-O-O Be7 24. b3 Here, black continued with the illegal move 24...,O-O, which wasn't noticed by both players. The game continued 25.Qxe7 Bb1 26.Rd2 Rxd2 27.Kxd2 Qd3+ 28.Ke1 Bc2 29. f4 Qxe3+ 30.Kf1 Bd3 mate