| Game |
| Result | Moves |
Year |
Event/Locale | Opening |
| 26. O De la Riva Aguado vs Krasenkow |
| ½-½ | 20 |
1998 |
Pamplona International | B06 Robatsch |
| 27. Illescas-Cordoba vs O De la Riva Aguado |
| 1-0 | 39 |
1998 |
Pamplona International | A81 Dutch |
| 28. O De la Riva Aguado vs J M De La Villa Garcia |
| ½-½ | 29 |
1998 |
Pamplona International | C06 French, Tarrasch |
| 29. G Timoshenko vs O De la Riva Aguado |
| ½-½ | 22 |
1998 |
Ubeda op 3rd | A80 Dutch |
| 30. L Comas Fabrego vs O De la Riva Aguado |
| ½-½ | 17 |
1998 |
Pamplona International | A39 English, Symmetrical, Main line with d4 |
| 31. M Ubezio vs O De la Riva Aguado |
| 0-1 | 58 |
1999 |
Saint Vincent Open | A86 Dutch |
| 32. Sutovsky vs O De la Riva Aguado |
| 1-0 | 32 |
1999 |
Pamplona International | B31 Sicilian, Rossolimo Variation |
| 33. O De la Riva Aguado vs F Castaldo |
| ½-½ | 21 |
1999 |
Saint Vincent Open | C11 French |
| 34. O De la Riva Aguado vs Xie Jun |
| 0-1 | 35 |
1999 |
Pamplona International | C45 Scotch Game |
| 35. I Novikov vs O De la Riva Aguado |
| 1-0 | 34 |
1999 |
Saint Vincent Open | A87 Dutch, Leningrad, Main Variation |
| 36. A Zinani vs O De la Riva Aguado |
| 0-1 | 34 |
1999 |
Saint Vincent Open | A81 Dutch |
| 37. A Scerbo vs O De la Riva Aguado |
| 0-1 | 37 |
1999 |
Saint Vincent Open | A89 Dutch, Leningrad, Main Variation with Nc6 |
| 38. Vallejo-Pons vs O De la Riva Aguado |
 | 0-1 | 34 |
1999 |
Pamplona International | A57 Benko Gambit |
| 39. O De la Riva Aguado vs Glek |
| 0-1 | 41 |
1999 |
Saint Vincent Open | C11 French |
| 40. O De la Riva Aguado vs Morozevich |
 | 0-1 | 34 |
1999 |
Pamplona International | B07 Pirc |
| 41. O De la Riva Aguado vs Ivanchuk |
| ½-½ | 23 |
2000 |
34th Olympiad | B42 Sicilian, Kan |
| 42. Shirov vs O De la Riva Aguado |
| 1-0 | 33 |
2001 |
Banc Agricol Blitz | B47 Sicilian, Taimanov (Bastrikov) Variation |
| 43. I Sofronie vs O De la Riva Aguado |
| 1-0 | 38 |
2001 |
open | B31 Sicilian, Rossolimo Variation |
| 44. O De la Riva Aguado vs G Rechlis |
| ½-½ | 18 |
2001 |
TCh-FRA | B51 Sicilian, Canal-Sokolsky (Rossolimo) Attack |
| 45. Ulf Andersson vs O De la Riva Aguado |
 | 1-0 | 41 |
2001 |
Pamplona ESP | A88 Dutch, Leningrad, Main Variation with c6 |
| 46. Shirov vs O De la Riva Aguado |
| 0-1 | 42 |
2001 |
Banc Agricol Blitz | A81 Dutch |
| 47. Anand vs O De la Riva Aguado |
| 1-0 | 44 |
2001 |
Rapidplay | A81 Dutch |
| 48. O De la Riva Aguado vs Shirov |
| 1-0 | 37 |
2001 |
Banc Agricol Blitz | B90 Sicilian, Najdorf |
| 49. O De la Riva Aguado vs Gorelov |
| ½-½ | 17 |
2001 |
open | C10 French |
| 50. A Jossien vs O De la Riva Aguado |
| 0-1 | 40 |
2001 |
TCh-FRA | A04 Reti Opening |