| Game |
| Result | Moves |
Year |
Event/Locale | Opening |
| 1. Miles vs R Dieks |
 | 1-0 | 21 |
1972 |
Groningen | B71 Sicilian, Dragon, Levenfish Variation |
| 2. Beliavsky vs R Dieks |
| 1-0 | 38 |
1973 |
Wch U20 fin-A | B90 Sicilian, Najdorf |
| 3. Beliavsky vs R Dieks |
| 1-0 | 53 |
1973 |
Wch U20 prel-A | B90 Sicilian, Najdorf |
| 4. R Dieks vs Keene |
| 0-1 | 60 |
1974 |
Hoogovens-B | A15 English |
| 5. Tarjan vs R Dieks |
| 0-1 | 46 |
1974 |
Wijk aan Zee II | E10 Queen's Pawn Game |
| 6. R Pye vs R Dieks |
| 0-1 | 47 |
1974 |
EU-ch U20 qual | B92 Sicilian, Najdorf, Opocensky Variation |
| 7. F Kuijpers vs R Dieks |
| ½-½ | 29 |
1974 |
Hoogovens-B | B93 Sicilian, Najdorf, 6.f4 |
| 8. R Dieks vs Nunn |
| 1-0 | 38 |
1974 |
Groningen | A75 Benoni, Classical with ...a6 and 10...Bg4 |
| 9. R Dieks vs Marjanovic |
| 0-1 | 32 |
1974 |
Manila (Philippines) | B44 Sicilian |
| 10. P J Winston vs R Dieks |
| 0-1 | 28 |
1974 |
Wch U20 | B96 Sicilian, Najdorf |
| 11. R Dieks vs P Du Chattel |
| 1-0 | 106 |
1975 |
30. NED-ch | A00 Uncommon Opening |
| 12. R Dieks vs Timman |
| 0-1 | 40 |
1975 |
3, Leeuwarden NED ch | B09 Pirc, Austrian Attack |
| 13. R Dieks vs A Van Dop |
| 1-0 | 34 |
1975 |
30. NED-ch | B84 Sicilian, Scheveningen |
| 14. F Borm vs R Dieks |
| ½-½ | 58 |
1975 |
30. NED-ch | B77 Sicilian, Dragon, Yugoslav Attack |
| 15. W Schmidt vs R Dieks |
| 1-0 | 47 |
1975 |
Hoogovens-B | A38 English, Symmetrical |
| 16. J Vogel vs R Dieks |
| ½-½ | 31 |
1975 |
30. NED-ch | E65 King's Indian, Fianchetto, Yugoslav, 7.O-O |
| 17. Schouten Nico vs R Dieks |
| 1-0 | 25 |
1975 |
30. NED-ch | A69 Benoni, Four Pawns Attack, Main line |
| 18. R Dieks vs B Enklaar |
| 1-0 | 38 |
1975 |
30. NED-ch | B83 Sicilian |
| 19. R Dieks vs V Ciocaltea |
| 0-1 | 35 |
1975 |
Hoogovens-B | C73 Ruy Lopez, Modern Steinitz Defense |
| 20. Van der Sterren vs R Dieks |
| 1-0 | 68 |
1975 |
30. NED-ch | B92 Sicilian, Najdorf, Opocensky Variation |
| 21. R Dieks vs H Bohm |
| ½-½ | 69 |
1975 |
30. NED-ch | B05 Alekhine's Defense, Modern |
| 22. H Ree vs R Dieks |
| 1-0 | 34 |
1975 |
30. NED-ch | E91 King's Indian |
| 23. R Hartoch vs R Dieks |
| ½-½ | 59 |
1975 |
30. NED-ch | B20 Sicilian |
| 24. R Dieks vs Van Eijbergen |
 | 1-0 | 8 |
1979 |
Dieren | A09 Reti Opening |
| 25. De Ruijter vs R Dieks |
| 1-0 | 21 |
1980 |
NLD m/27 | C31 King's Gambit Declined, Falkbeer Counter Gambit |