| ECO B66 in 1975 play it! zuidema coenraad defeats black's bellin robert in 85 moves | 1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 Nc6 6. Bg5 e6 7. Qd2 a6 8. O-O-O h6 9. Be3 Bd7 10. f4 b5 11. Bd3 b4 12. Nce2 Qb8 13. Kb1 Qb7 14. Nf3 e5 15. h3 Be6 16. f5 Bd7 17. g4 Na7 18. Bxa7 Rxa7 19. Ng3 Be7 20. Rhe1 a5 21. Bc4 Qc6 22. b3 Bc8 23. g5 hxg5 24. Nxg5 Bf8 25. Qe3 Rc7 26. Qd3 Qc5 27. Rc1 Nh5 28. Nxh5 Rxh5 29. Qg3 Qa7 30. c3 Ba6 31. Bxa6 Qxa6 32. cxb4 Rxc1+ 33. Rxc1 axb4 34. Nxf7 Kxf7 35. Qg6+ Kg8 36. Qxh5 Qd3+ 37. Rc2 Qxe4 38. Qg4 Qe1+ 39. Rc1 Qd2 40. Rd1 Qh6 41. Qxb4 Qxh3 42. Qc4+ Kh8 43. Qe4 |
| ECO B33 in 1972 play it! zuidema coenraad defeats black's van den berg a in 77 moves | 1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 e6 6. Ndb5 Bb4 7. a3 Bxc3+ 8. Nxc3 d5 9. exd5 exd5 10. Bd3 O-O 11. O-O d4 12. Ne2 Ng4 13. b4 a6 14. h3 Nge5 15. Bb2 Bxh3 16. gxh3 Nf3+ 17. Kh1 Qh4 18. Ng1 Nxg1 19. Kxg1 Qxh3 20. Be4 Rad8 21. Qf3 Qh4 22. Qh1 Qg5+ 23. Qg2 Qh4 24. Qh1 Qg5+ 25. Qg2 Qh4 26. Rad1 f5 27. Bd5+ Kh8 28. Rd3 Rd6 29. Re1 Qd8 30. c4 Rff6 31. Rg3 f4 32. Rg4 Rg6 33. Bf7 f3 34. Rxg6 Rxg6 35. Qxg6 hxg6 36. Re8+ Qxe8 37. Bxe8 Ne5 38. c5 d3 39. Bxe5 |
| ECO B57 in 1967 play it! zuidema coenraad defeats black's ree hans in 21 moves | 1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 Nc6 6. Bc4 Bd7 7. Be3 Ng4 8. O-O Nxe3 9. fxe3 Ne5 10. Qh5 g6 11. Qxe5 |
| ECO B42 in 1964 play it! zuidema coenraad defeats black's filip miroslav in 63 moves | 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 a6 5. Bd3 Nf6 6. O-O d6 7. Nc3 Nbd7 8. Be3 b5 9. f4 Bb7 10. Qf3 Rc8 11. Rae1 Be7 12. g4 Rxc3 13. bxc3 Nc5 14. Nxe6 Nxe6 15. g5 Nd7 16. Bd4 Ndc5 17. Qe3 O-O 18. Rf3 f5 19. exf5 Nxd4 20. cxd4 Nxd3 21. Qe6+ Kh8 22. Rxd3 Bxg5 23. fxg5 Qxg5+ 24. Rg3 Qd2 25. Qe3 Qxe3+ 26. Rexe3 Bc8 27. Re7 Bxf5 28. Rgxg7 Bxc2 29. Ra7 Be4 30. Rgd7 d5 31. Rxa6 Rg8+ 32. Kf2 |
| ECO B46 in 1962 play it! zuidema coenraad defeats black's calvo minguez ri in 35 moves | 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 a6 6. Be3 Qc7 7. a3 Nf6 8. f4 d6 9. Qf3 Be7 10. Bd3 e5 11. Nde2 b5 12. O-O O-O 13. f5 Bb7 14. Nd5 Nxd5 15. exd5 e4 16. Qxe4 Rfe8 17. dxc6 d5 18. Qg4 |
| ECO B42 in 1971 play it! zuidema coenraad defeats black's enklaar bert in 80 moves | 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 a6 5. Bd3 Bc5 6. Nb3 Ba7 7. O-O Ne7 8. Qe2 Nbc6 9. Be3 Bxe3 10. Qxe3 O-O 11. N1d2 e5 12. Nc4 d5 13. exd5 Nxd5 14. Qc5 Nf4 15. Be4 Qg5 16. g3 Be6 17. Kh1 Nh3 18. Bg2 Rad8 19. Rae1 Qf6 20. Nxe5 Nxe5 21. Rxe5 Nxf2+ 22. Kg1 Rd1 23. Rxd1 Nxd1 24. Re1 Bxb3 25. Rxd1 b6 26. Qc7 Bxa2 27. b3 a5 28. Qd7 Qc3 29. Qc6 Qe3+ 30. Kh1 g6 31. Bd5 Qf2 32. Qc4 b5 33. Qxb5 Qxc2 34. Rf1 Qc7 35. Qa4 Qd8 36. Rd1 Qg5 37. Qxa2 Rd8 38. Qd2 Qxd2 39. Rxd2 Kg7 40. Rd3 Rb8 |
| ECO B43 in 1964 play it! zuidema coenraad defeats black's szabo laszlo hun in 81 moves | 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 a6 5. Nc3 b5 6. Bd3 Bb7 7. O-O Bc5 8. Nb3 Ba7 9. a4 b4 10. Na2 Nc6 11. a5 Qh4 12. Qd2 h6 13. Nxb4 Nf6 14. Nxc6 Bxc6 15. Qf4 Qxf4 16. Bxf4 Nxe4 17. Rae1 f5 18. Be3 Kf7 19. f3 Bxe3+ 20. Rxe3 Nf6 21. Nc5 Rhb8 22. b3 Nd5 23. Re2 Nf4 24. Rd2 d6 25. Nxa6 Rb7 26. Bc4 Bd5 27. Bb5 Rxb5 28. Nc7 Rbxa5 29. Nxa8 Bxa8 30. Rxd6 Ra2 31. Rf2 Ke7 32. Rd1 Rb2 33. Rfd2 Bc6 34. Kf2 g5 35. g3 Nh3+ 36. Ke2 e5 37. Ra1 e4 38. fxe4 fxe4 39. Ke3 Be8 40. Kd4 e3 41. Re2 |
| ECO B45 in 1984 play it! zuidema coenraad defeats black's ligterink gert in 71 moves | 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 d6 6. Be2 Nf6 7. O-O Be7 8. f4 O-O 9. Be3 Bd7 10. Nb3 Qc7 11. Bf3 Rfd8 12. Qe1 Be8 13. Nb5 Qb8 14. c4 a6 15. Nc3 Nd7 16. Qe2 Nc5 17. Nd4 Rc8 18. Rac1 b5 19. Nxc6 Bxc6 20. Bxc5 dxc5 21. e5 Qb7 22. Bxc6 Qxc6 23. Rfd1 b4 24. Ne4 Rd8 25. Qf3 Kf8 26. f5 exf5 27. Qxf5 Kg8 28. Qf3 Kf8 29. Rf1 Qe6 30. Rc2 Kg8 31. Nd6 Bxd6 32. exd6 Ra7 33. Rd2 Rxd6 34. Qf4 Rad7 35. Rfd1 g5 36. Qxg5+ |
| ECO B41 in 1972 play it! zuidema coenraad defeats black's ree hans in 95 moves | 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 d6 6. Bd3 Nc6 7. Nb3 a6 8. a4 b6 9. O-O Bb7 10. f4 Be7 11. Qf3 O-O 12. Qh3 Re8 13. Kh1 Bf8 14. Bd2 Nd7 15. e5 g6 16. Ne4 f5 17. exf6 Nxf6 18. Ng5 Qd7 19. Bc3 Nd5 20. Bxg6 Re7 21. Nxh7 Rxh7 22. Bxh7+ Qxh7 23. Qxe6+ Qf7 24. Qg4+ Bg7 25. Bxg7 Qxg7 26. Qe6+ Qf7 27. Qg4+ Qg7 28. Qxg7+ Kxg7 29. Rae1 Rf8 30. f5 Bc8 31. g4 Ne5 32. h3 Rh8 33. Kg2 Nc4 34. Kg3 Nxb2 35. Re4 b5 36. axb5 axb5 37. Nd4 Bd7 38. Ne6+ Kf7 39. Nf4 Nc3 40. Re3 Nbd1 41. Ree1 Nb2 42. Ng6 Re8 43. Rxe8 Bxe8 44. Re1 Bc6 45. Re7+ Kf6 46. Rc7 Ne4+ 47. Kf4 Bd5 48. h4 |
| ECO B32 in 1966 play it! zuidema coenraad defeats black's freeman michael in 59 moves | 1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. Nc3 a6 6. Be2 Qc7 7. f4 Bc5 8. Be3 d6 9. Qd2 Bd7 10. O-O-O b5 11. Bxb5 axb5 12. Ndxb5 Qd8 13. Bxc5 dxc5 14. Nd6+ Ke7 15. Nb7 Qc7 16. Nb5 Rxa2 17. Kb1 Rxb2+ 18. Kxb2 Qxb7 19. Qd6+ Ke8 20. Kc1 Nf6 21. e5 Nxe5 22. fxe5 Qxb5 23. exf6 gxf6 24. Rd3 c4 25. Rd4 Qa4 26. Rhd1 Qa1+ 27. Kd2 Qa5+ 28. Ke2 Qh5+ 29. Kf2 Qf5+ 30. Kg1 |
| ECO B32 in 1963 play it! zuidema coenraad defeats black's de rooi paul in 81 moves | 1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e5 5. Nb5 a6 6. Nd6+ Bxd6 7. Qxd6 Qf6 8. Qa3 Qg6 9. Be3 b5 10. Nd2 b4 11. Qd3 Nge7 12. Nc4 O-O 13. Nd6 Nd4 14. Nxc8 Rfxc8 15. Bxd4 exd4 16. g3 Nc6 17. Bg2 Ne5 18. Qxd4 Qf6 19. O-O-O Rc4 20. Qd5 Rac8 21. Rd2 Nf3 22. e5 Nxe5 23. f4 Ng6 24. Qxd7 R4c7 25. Qa4 Qf5 26. Rhd1 h6 27. Bf1 Nf8 28. Kb1 a5 29. Ba6 Ra8 30. Bd3 Qe6 31. Re2 Qg4 32. Rde1 Ne6 33. Re5 g6 34. Rxa5 Rd8 35. Ra8 Rxa8 36. Qxa8+ Kg7 37. Qe4 Re7 38. Qxb4 Nc5 39. Qd4+ Kh7 40. Bxg6+ Qxg6 41. Rxe7 |
| ECO B42 in 1966 play it! zuidema coenraad defeats black's minaya molano ju in 119 moves | 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 a6 5. Bd3 Qc7 6. O-O b5 7. Qe2 Bb7 8. a4 bxa4 9. Rxa4 d6 10. Nd2 Nf6 11. N2b3 Nbd7 12. Rc4 Qb6 13. Be3 Nc5 14. Nxc5 dxc5 15. Nb3 Rc8 16. Ra4 Be7 17. Na5 O-O 18. Nxb7 Qxb7 19. Bxa6 Qc6 20. b3 Rb8 21. Bd3 Rb4 22. Ra6 Qb7 23. Rfa1 Qb8 24. Bd2 Rb6 25. f4 Rxa6 26. Rxa6 Rd8 27. g3 Qb7 28. Ra1 c4 29. bxc4 Bc5+ 30. Kg2 h5 31. Qf3 Nxe4 32. Bxe4 Rxd2+ 33. Kh3 Qd7 34. Ra8+ Bf8 35. Qa3 Qd6 36. Qxd6 Rxd6 37. c5 Rd7 38. c6 Rc7 39. Rd8 g6 40. Kg2 Kg7 41. Kf1 Bc5 42. h4 Kf6 43. Bg2 Ke7 44. Rd3 Ba7 45. Ke2 Bc5 46. Kd2 Ra7 47. Kc1 Ra1+ 48. Kb2 Ra7 49. c3 Bd6 50. Bf3 Rc7 51. Kb3 Ra7 52. Kc4 Bc7 53. Bd1 Bd8 54. Bb3 Ba5 55. Ba4 Bd8 56. Kb4 Ba5+ 57. Kc5 Bxc3 58. Rxc3 Rxa4 59. c7 Kd7 60. c8=Q+ |
| ECO B42 in 1970 play it! zuidema coenraad defeats black's rohrl carl in 93 moves | 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 a6 5. Bd3 Bc5 6. Nb3 Ba7 7. O-O Nc6 8. Qe2 Qf6 9. Be3 Bxe3 10. Qxe3 Nge7 11. f4 e5 12. fxe5 Qxe5 13. N1d2 Ng6 14. Nc4 Qe7 15. Nd4 Nxd4 16. Qxd4 O-O 17. a4 d6 18. Qxd6 Be6 19. e5 Qg5 20. Bxg6 hxg6 21. Qd2 Qh5 22. Nb6 Rad8 23. Qe3 Qg4 24. c3 Bf5 25. h3 Qh4 26. Rad1 Rxd1 27. Rxd1 Rd8 28. Nd5 Rd7 29. Rd4 Qd8 30. Nf4 g5 31. Ne2 Be6 32. Ng3 Qb6 33. b4 a5 34. bxa5 Qb1+ 35. Kh2 Rxd4 36. Qxd4 Qc1 37. Ne2 Qc2 38. Ng1 g4 39. hxg4 Qc1 40. Nf3 Kh7 41. Kg3 g6 42. Qd2 Qa3 43. Ng5+ Kg7 44. Nxe6+ fxe6 45. Qd7+ Kh6 46. Qc8 Kg7 47. Qxb7+ |
| ECO B43 in 1965 play it! zuidema coenraad defeats black's franco raymundo in 61 moves | 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 a6 5. Nc3 Qc7 6. Be2 b5 7. O-O d6 8. a4 b4 9. Na2 Nf6 10. Bf3 e5 11. Ne2 Nc6 12. Bd2 Rb8 13. c3 b3 14. Nb4 Nxb4 15. cxb4 d5 16. Ng3 d4 17. Qxb3 Be6 18. Qd3 Bc4 19. Rfc1 Bxd3 20. Rxc7 Bd6 21. Rcc1 a5 22. b5 Kd7 23. Bxa5 Rhc8 24. Bd1 Rxc1 25. Rxc1 Nxe4 26. Bg4+ Ke8 27. Bf5 Nc5 28. Rxc5 Bxc5 29. Bxd3 h6 30. b4 Bf8 31. b6 |
| ECO B47 in 1973 play it! zuidema coenraad defeats black's langeweg kick in 113 moves | 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 Qc7 6. g3 a6 7. Bg2 Nf6 8. O-O Be7 9. Re1 Nxd4 10. Qxd4 Bc5 11. Qd1 d6 12. Be3 e5 13. Bxc5 Qxc5 14. Qd2 Be6 15. Rad1 Ke7 16. Re3 Rac8 17. Na4 Qc7 18. Rc3 Qb8 19. Nb6 Rc6 20. Rxc6 bxc6 21. Qa5 Qa7 22. c4 c5 23. b4 Qc7 24. bxc5 Qxc5 25. Qxa6 Rb8 26. Na4 Qc7 27. c5 dxc5 28. Nc3 Qb6 29. Qe2 Kf8 30. h3 c4 31. Kh2 Qa5 32. Qd2 Ke8 33. Qd6 Rc8 34. Nd5 Qc5 35. Qxe5 c3 36. Rc1 c2 37. Qf4 Nxd5 38. exd5 Bxd5 39. Qa4+ Ke7 40. Bxd5 Qxd5 41. Rxc2 Rxc2 42. Qxc2 h5 43. h4 g5 44. hxg5 Qxg5 45. Qe4+ Kf8 46. a4 Qc5 47. Qe3 Qb4 48. Qh6+ Kg8 49. Qg5+ Kf8 50. Qxh5 Qxa4 51. Qh8+ Ke7 52. Qh4+ Qxh4+ 53. gxh4 Kf6 54. Kg3 Kf5 55. Kf3 Kg6 56. Kg4 Kh6 57. h5 |
| ECO B35 in 1972 play it! zuidema coenraad defeats black's jongsma lex in 93 moves | 1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 g6 5. Nc3 Bg7 6. Be3 Nf6 7. Bc4 O-O 8. Bb3 a5 9. f3 d5 10. Bxd5 Qb6 11. Na4 Qa6 12. Bxc6 bxc6 13. Qe2 Qb7 14. O-O Nd7 15. c4 Rb8 16. Rac1 c5 17. Nb5 Qc6 18. Rfd1 Bd4 19. Nac3 e5 20. Nd5 Qe6 21. b3 Bb7 22. Nbc7 Qd6 23. Nb5 Qe6 24. Nbc7 Qd6 25. Bxd4 exd4 26. f4 Bxd5 27. Nxd5 f6 28. Rd3 Rfe8 29. Re1 Kg7 30. Rg3 Kh8 31. h4 Re6 32. h5 f5 33. e5 Qc6 34. hxg6 hxg6 35. Qf2 Kg7 36. Rh3 Rh8 37. Rxh8 Kxh8 38. Qh4+ Kg7 39. Kf2 a4 40. Rh1 Nf8 41. Nc7 axb3 42. Nxe6+ Qxe6 43. axb3 Kf7 44. Ra1 Qb6 45. Ra8 d3 46. Qh6 Ne6 47. Qh7+ |
| ECO B45 in 1973 play it! zuidema coenraad defeats black's enklaar bert in 79 moves | 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 d6 6. Be2 Nf6 7. O-O Be7 8. Be3 O-O 9. f4 Bd7 10. Nb3 Qc7 11. Kh1 a6 12. a4 b6 13. Bf3 Rab8 14. Qe2 Na5 15. Nd2 Bc8 16. Bf2 Nd7 17. Rad1 Bf6 18. Ndb1 Bb7 19. Bd4 Rbc8 20. Bxf6 Nxf6 21. Na3 Rfd8 22. Qf2 e5 23. f5 Nc6 24. Nd5 Nxd5 25. exd5 Nd4 26. f6 gxf6 27. Bh5 Qe7 28. Rd3 Rc7 29. Bd1 Bc8 30. c3 Nf5 31. Rf3 Ng7 32. Rxf6 Ne8 33. Rh6 f5 34. g4 f4 35. Bc2 Qf8 36. Bxh7+ Kg7 37. Qh4 Qe7 38. Rg6+ Kf7 39. Qh6 Qf8 40. Bg8+ |
| ECO B33 in 1963 play it! zuidema coenraad defeats black's mohrlok dieter in 49 moves | 1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 d6 6. Bg5 e6 7. Qd2 Be7 8. O-O-O O-O 9. f4 Nxd4 10. Qxd4 Qa5 11. Bc4 Rd8 12. Rhf1 Bd7 13. f5 b5 14. fxe6 bxc4 15. Rf5 Qb4 16. exf7+ Kxf7 17. Bxf6 Bxf5 18. Bxe7 Be6 19. Bxd8 Rxd8 20. Qxa7+ Rd7 21. Rf1+ Kg6 22. Qf2 Rf7 23. Qg3+ Kh6 24. Rxf7 Bxf7 25. Qh4+ |
| ECO B34 in 1966 play it! zuidema coenraad defeats black's szabo laszlo in 91 moves | 1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 g6 5. Nc3 Bg7 6. Be3 d6 7. Qd2 Nf6 8. f3 Bd7 9. O-O-O a6 10. g4 Rc8 11. Nxc6 Bxc6 12. Bd4 O-O 13. h4 Qa5 14. Kb1 Rfd8 15. Qe3 Nd7 16. Bxg7 Kxg7 17. h5 Qc5 18. Qc1 Rh8 19. Nd5 Bxd5 20. h6+ Kg8 21. Rxd5 Qf2 22. Qd1 f6 23. g5 Kf7 24. Bh3 Rc7 25. Bxd7 Rxd7 26. gxf6 Kxf6 27. e5+ Ke6 28. Re1 Qxe1 29. Qxe1 Kxd5 30. e6 Rdd8 31. Qe4+ Kc5 32. Qxb7 Rhe8 33. Qxa6 Rb8 34. a3 Kd5 35. Qe2 Rf8 36. Qe4+ Kc5 37. b4+ Kb6 38. Qd4+ Kc6 39. Kb2 Rf6 40. Qa7 Rb7 41. Qa6+ Kc7 42. Qa5+ Kb8 43. Qd8+ Ka7 44. Qh8 Rc7 45. Qxh7 Rxe6 46. Qg7 |
| ECO B43 in 1964 play it! zuidema coenraad defeats black's janosevic dragol in 107 moves | 1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 a6 5. Nc3 Qc7 6. Be2 Nc6 7. f4 b5 8. Nxc6 Qxc6 9. Bf3 Bb7 10. Be3 Rc8 11. O-O Bc5 12. Qe1 Ne7 13. e5 Bxe3+ 14. Qxe3 Qc7 15. Ne4 Nf5 16. Nd6+ Qxd6 17. Qa7 Qd4+ 18. Qxd4 Nxd4 19. Bxb7 Rxc2 20. Rf2 Ke7 21. Rd1 Rb8 22. Be4 Rxf2 23. Kxf2 Nf5 24. g4 Nh4 25. Bxh7 Rc8 26. Kg3 Ng6 27. Rd2 Rf8 28. Bxg6 fxg6 29. Kh4 a5 30. Kg5 Rc8 31. h3 Rh8 32. Rc2 Rxh3 33. Rc5 b4 34. b3 Kf7 35. Rxa5 Rd3 36. Ra4 Rd2 37. Rxb4 Rxa2 38. Rb7 Rd2 39. Rb6 Rg2 40. Rd6 Ke7 41. b4 Rb2 42. Rd4 Rg2 43. b5 Rb2 44. Kxg6 Rxb5 45. Kxg7 Rb1 46. g5 Rg1 47. g6 Rg2 48. Ra4 Rg1 49. Rd4 Rf1 50. Kh7 Rh1+ 51. Kg8 Rg1 52. g7 Rh1 53. Rxd7+ Kxd7 54. Kf8 |