| Game |
| Result | Moves |
Year |
Event/Locale | Opening |
| 1. DeFirmian vs J L Arnason |
| 0-1 | 31 |
1973 |
Bunadarbanka (Iceland) | C72 Ruy Lopez, Modern Steinitz Defense, 5.O-O |
| 2. DeFirmian vs Silman |
 | 0-1 | 35 |
1976 |
Lone Pine (USA) | C92 Ruy Lopez, Closed |
| 3. DeFirmian vs Martinovsky |
| 1-0 | 51 |
1976 |
Lone Pine (USA) | C62 Ruy Lopez, Old Steinitz Defense |
| 4. DeFirmian vs R C Balinas |
| 0-1 | 36 |
1978 |
London (England) | C60 Ruy Lopez |
| 5. DeFirmian vs Christiansen |
| 1-0 | 46 |
1979 |
Lone Pine (USA) | C72 Ruy Lopez, Modern Steinitz Defense, 5.O-O |
| 6. DeFirmian vs P Nikolic |
| 0-1 | 39 |
1980 |
Olympiad | C92 Ruy Lopez, Closed |
| 7. DeFirmian vs Ivkov |
| 1-0 | 44 |
1981 |
Baden-Baden (Germany) | C72 Ruy Lopez, Modern Steinitz Defense, 5.O-O |
| 8. DeFirmian vs S Djuric |
| ½-½ | 41 |
1983 |
It ( cat. 10 ) | C97 Ruy Lopez, Closed, Chigorin |
| 9. DeFirmian vs Z Nikolic |
| ½-½ | 23 |
1983 |
Vrnjachka Banja (Yugoslavia) | C98 Ruy Lopez, Closed, Chigorin |
| 10. DeFirmian vs G Agzamov |
| 0-1 | 30 |
1983 |
Stara | C80 Ruy Lopez, Open |
| 11. DeFirmian vs Smejkal |
| ½-½ | 59 |
1983 |
It (cat.10) | C95 Ruy Lopez, Closed, Breyer |
| 12. DeFirmian vs G Agzamov |
| 0-1 | 38 |
1983 |
Vrsac | C80 Ruy Lopez, Open |
| 13. DeFirmian vs M Knezevic |
| 1-0 | 32 |
1984 |
Bunadarbanka (Iceland) | C67 Ruy Lopez |
| 14. DeFirmian vs J Kristiansen |
| 1-0 | 25 |
1984 |
Bunadarbanka (Iceland) | C80 Ruy Lopez, Open |
| 15. DeFirmian vs Hjartarson |
| 0-1 | 69 |
1984 |
Reykjavik (Iceland) | C92 Ruy Lopez, Closed |
| 16. DeFirmian vs Jansa |
| ½-½ | 13 |
1984 |
Bor (07) | C84 Ruy Lopez, Closed |
| 17. DeFirmian vs Ivkov |
| 0-1 | 50 |
1984 |
09 | C96 Ruy Lopez, Closed |
| 18. DeFirmian vs J L Arnason |
| 0-1 | 59 |
1984 |
Oslo (Norway) | C96 Ruy Lopez, Closed |
| 19. DeFirmian vs Huebner |
| ½-½ | 39 |
1984 |
Oslo (Norway) | C80 Ruy Lopez, Open |
| 20. DeFirmian vs P Nikolic |
| 1-0 | 37 |
1985 |
Tunis | C92 Ruy Lopez, Closed |
| 21. DeFirmian vs Beliavsky |
| 0-1 | 40 |
1985 |
Izt | C92 Ruy Lopez, Closed |
| 22. DeFirmian vs P Nikolic |
| 0-1 | 52 |
1986 |
Reykjavik (Iceland) | C99 Ruy Lopez, Closed, Chigorin, 12...cd |
| 23. DeFirmian vs I Rogers |
| 1-0 | 33 |
1986 |
Philadelphia (USA) | C64 Ruy Lopez, Classical |
| 24. DeFirmian vs H Ree |
| 0-1 | 62 |
1986 |
Wijk aan Zee (Netherlands) | C90 Ruy Lopez, Closed |
| 25. DeFirmian vs Zsuzsa Polgar |
| 1-0 | 32 |
1986 |
It (open) | C76 Ruy Lopez, Modern Steinitz Defense, Fianchetto Variation |
