[Event "Dortmunder Schachtage-01"]
[Site "Dortmund"]
[Date "1973.06.05"]
[Round "4"]
[White "Bachmann, Friedhelm"]
[Black "Ostermeyer, Peter"]
[Result "1/2-1/2"]

1. c4 Nf6 2. Nf3 g6 3. g3 Bg7 4. Bg2 O-O 5. O-O d6 6. Nc3 e5 7. d3 c6 8. Rb1 a5 9. a3 Re8 10. Bg5 h6 11. Bxf6 Bxf6 12. b4 axb4 13. axb4 Bg7 14. Qb3 Be6 15. b5 Nd7 16. Nd2 Nc5 17. Qb4 Qd7 18. Nde4 Nxe4 19. bxc6 bxc6 20. Bxe4 d5 21. cxd5 cxd5 22. Bg2 Rec8 23. e4 Bf8 24. Qb2 d4 25. Nd5 Bxd5 26. exd5 Ra3 1/2-1/2