[Event "Piatigorsky-Cup 2nd"]
[Site "Santa Monica"]
[Date "1966.07.17"]
[Round "1"]
[White "Donner, Jan Hein"]
[Black "Unzicker, Wolfgang"]
[Result "1/2-1/2"]

1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 O-O 5. Bd3 d5 6. Nf3 c5 7. O-O dxc4 8. Bxc4 Nbd7 9. Qe2 a6 10. a3 Ba5 11. Bd3 Bc7 12. Rd1 Qe7 13. dxc5 Nxc5 14. Bc2 Ncd7 15. Bd2 Rd8 16. Rac1 Nf8 17. e4 e5 18. Bg5 Be6 19. Nh4 h6 20. Nf5 Bxf5 21. Bxf6 Qxf6 22. exf5 Rd4 23. Be4 Bb6 24. Bxb7 Ra7 25. Be4 Rad7 26. Nd5 Qd8 27. Qf3 Nh7 28. Rxd4 Bxd4 29. f6 Nxf6 30. Nxf6+ gxf6 31. Bf5 Rc7 32. Rd1 a5 33. h4 Qb8 34. b4 axb4 35. Rb1 Rc3 36. Qg4+ Kf8 37. axb4 Qa7 38. Qe2 Ra3 39. Rc1 Ra1 40. Rxa1 Qxa1+ 41. Kh2 Bb6 42. Qd2 Kg7 43. Kg3 1/2-1/2