| Game |
| Result | Moves |
Year | Event/Locale | Opening |
| 1. H Holaszek vs O Jakobsen |
| 1-0 | 73 | 1961 | Wch U20 prel-A | B48 Sicilian, Taimanov Variation |
| 2. W Schmidt vs H Holaszek |
| 1-0 | 17 | 1961 | Wch U20 prel-A | C77 Ruy Lopez |
| 3. Gheorghiu vs H Holaszek |
| 1-0 | 36 | 1961 | Wch U20 prel-A | E70 King's Indian |
| 4. H Holaszek vs B Nagy |
| 1-0 | 23 | 1961 | Wch U20 prel-A | B75 Sicilian, Dragon, Yugoslav Attack |
| 5. H Holaszek vs J Minaya |
| ½-½ | 39 | 1961 | Wch U20 fin-B | B68 Sicilian, Richter-Rauzer Attack, 7...a6 Defense, 9...Be7 |
| 6. D Smith vs H Holaszek |
| 1-0 | 35 | 1961 | Wch U20 fin-B | E70 King's Indian |
| 7. A Rosino vs H Holaszek |
| ½-½ | 21 | 1961 | Wch U20 fin-B | E81 King's Indian, Samisch |
| 8. H Holaszek vs L Gilden |
| 0-1 | 41 | 1961 | Wch U20 fin-B | B42 Sicilian, Kan |
| 9. O Jakobsen vs H Holaszek |
| ½-½ | 39 | 1961 | Wch U20 fin-B | C35 King's Gambit Accepted, Cunningham |
| 10. H Holaszek vs J R Phillips |
| 0-1 | 40 | 1961 | Wch U20 fin-B | C78 Ruy Lopez |
| 11. D Mohrlok vs H Holaszek |
| ½-½ | 30 | 1964 | Clare Benedict Cup | C84 Ruy Lopez, Closed |
| 12. H Holaszek vs J Barendregt |
| ½-½ | 44 | 1964 | Clare Benedict Cup | C41 Philidor Defense |
| 13. M Bonfioli vs H Holaszek |
| 0-1 | 36 | 1964 | Clare Benedict Cup | C95 Ruy Lopez, Closed, Breyer |
| 14. H Holaszek vs B Kurajica |
| ½-½ | 17 | 1964 | Zurich - jungmeister | B43 Sicilian, Kan, 5.Nc3 |
| 15. H Pfleger vs H Holaszek |
| 1-0 | 31 | 1964 | Zurich - jungmeister | C45 Scotch Game |
| 16. H Holaszek vs C Zuidema |
| ½-½ | 24 | 1964 | Zurich - jungmeister | C56 Two Knights |
| 17. M Janata vs H Holaszek |
| ½-½ | 32 | 1964 | Zurich - jungmeister | C44 King's Pawn Game |
| 18. H Holaszek vs O Kinnmark |
| 1-0 | 40 | 1964 | Zurich - jungmeister | C49 Four Knights |
| 19. F Tejero Royo vs H Holaszek |
| 0-1 | 40 | 1964 | Zurich - jungmeister | E80 King's Indian, Samisch Variation |
| 20. H Holaszek vs O Jakobsen |
| 0-1 | 35 | 1964 | Zurich - jungmeister | B84 Sicilian, Scheveningen |
| 21. P N Lee vs H Holaszek |
| ½-½ | 57 | 1964 | Zurich - jungmeister | C94 Ruy Lopez, Closed, Breyer Defense |
| 22. H Holaszek vs H Glauser |
| 1-0 | 31 | 1964 | Zurich - jungmeister | C45 Scotch Game |
| 23. M Markus vs H Holaszek |
| ½-½ | 15 | 1964 | Zurich - jungmeister | B01 Scandinavian |
| 24. E Eichhorn vs H Holaszek |
| 0-1 | 37 | 1964 | Zurich - jungmeister | B07 Pirc |
| 25. J Diez del Corral vs H Holaszek |
 | 1-0 | 62 | 1965 | Clare Benedict Cup | C85 Ruy Lopez, Exchange Variation Doubly Deferred (DERLD) |
Kibitzing
