| Game |
| Result | Moves |
Year | Event/Locale | Opening |
| 1. M Ruefenacht vs M J Mateus |
| 1-0 | 25 | 1984 | Thessaloniki Olympiad | B89 Sicilian |
| 2. M J Mateus vs M Saleh |
| 1-0 | 29 | 1984 | Thessaloniki Olympiad | E06 Catalan, Closed, 5.Nf3 |
| 3. Mario Psaila vs M J Mateus |
| 0-1 | 38 | 1984 | Thessaloniki Olympiad | D35 Queen's Gambit Declined |
| 4. A Tarazi vs M J Mateus |
| 0-1 | 65 | 1984 | Thessaloniki Olympiad | B51 Sicilian, Canal-Sokolsky (Rossolimo) Attack |
| 5. M J Mateus vs R Lau |
| 0-1 | 63 | 1986 | Dubai Olympiad | E12 Queen's Indian |
| 6. M J Mateus vs J Vaglio Munoz |
| ½-½ | 18 | 1986 | Dubai Olympiad | D33 Queen's Gambit Declined, Tarrasch |
| 7. M J Mateus vs Z Rahman |
| ½-½ | 69 | 1988 | Thessaloniki Olympiad | B06 Robatsch |
| 8. M J Mateus vs J E Ostos |
| 0-1 | 23 | 1988 | Thessaloniki Olympiad | C18 French, Winawer |
| 9. M J Mateus vs G Soppe |
| 0-1 | 30 | 1990 | Novi Sad Olympiad | E12 Queen's Indian |
| 10. J K Watson vs M J Mateus |
| 0-1 | 56 | 1990 | Novi Sad Olympiad | A05 Reti Opening |
| 11. M J Mateus vs B Nickoloff |
| 0-1 | 28 | 1990 | Novi Sad Olympiad | E11 Bogo-Indian Defense |
| 12. M J Mateus vs B Ziska |
| ½-½ | 26 | 1990 | Novi Sad Olympiad | E92 King's Indian |
| 13. H Hamdouchi vs M J Mateus |
| 1-0 | 43 | 1990 | Novi Sad Olympiad | B86 Sicilian, Fischer-Sozin Attack |
| 14. M J Mateus vs J Norri |
| 0-1 | 40 | 1991 | World Youth U26 Team Championship | C84 Ruy Lopez, Closed |
| 15. M J Mateus vs J Pelikian |
| 1-0 | 52 | 1991 | World Youth U26 Team Championship | B52 Sicilian, Canal-Sokolsky (Rossolimo) Attack |
| 16. M J Mateus vs A Riline Orso |
| 0-1 | 40 | 1991 | World Youth U26 Team Championship | B23 Sicilian, Closed |
| 17. G Curi vs M J Mateus |
| 1-0 | 59 | 1991 | World Youth U26 Team Championship | D87 Grunfeld, Exchange |
| 18. M J Mateus vs L Sepulveda |
| ½-½ | 53 | 1991 | World Youth U26 Team Championship | B30 Sicilian |
| 19. D Adla vs M J Mateus |
| 1-0 | 32 | 1991 | World Youth U26 Team Championship | B86 Sicilian, Fischer-Sozin Attack |
| 20. G Timoscenko vs M J Mateus |
| 1-0 | 34 | 1992 | Cappelle Open | D37 Queen's Gambit Declined |
| 21. M J Mateus vs J Seret |
| 0-1 | 54 | 1992 | Cappelle Open | B06 Robatsch |
| 22. M J Mateus vs D Couche |
| ½-½ | 36 | 1992 | Cappelle Open | C07 French, Tarrasch |
| 23. M J Mateus vs J Degraeve |
| 0-1 | 27 | 1992 | Cappelle Open | B31 Sicilian, Rossolimo Variation |
| 24. F Dessenne vs M J Mateus |
| ½-½ | 43 | 1992 | Cappelle Open | B40 Sicilian |
| 25. M J Mateus vs V Malisauskas |
| 0-1 | 26 | 1992 | Manila Olympiad | B92 Sicilian, Najdorf, Opocensky Variation |
Kibitzing
