Tous les combattants
 | Oleg Borisov | 2-1-0 REC | #2683 |  |
 | Oleg Dadonov | 1-1-0 REC | #2097 | |
 | Oleg Nagorny | 0-1-0 REC | #7581 |  |
 | Oleg Olenichev | 0-1-0 REC | #5920 | |
 | Oleg Popov | 7-1-0 REC | #1167 | |
 | Oleg Sanakoev | 0-1-0 REC | #8226 | |
 | Oleg Taktarov | 6-2-1 UFC | #1848 | |
 | Oļegs Jemeļjanovs | 0-2-0 REC | #6251 |  |
 | Oleksandr Moisa | 2-1-0 REC | #1294 | |
 | Oleksii Polischuck | 4-4-0 REC | #1831 | |
 | Olena Kolesnyk | 4-4-0 REC | #3385 | |
 | Olendet Apouassa Romeo | 0-1-0 REC | #5693 |  |
 | Olga Rubin | 4-3-0 REC | #2265 | |
 | Oli Thompson | 0-2-0 UFC | #5195 |  |
 | Oliver Enkamp | 0-2-0 UFC | #3821 |  |
 | Oliver Tero | 1-1-0 REC | #2146 | |
 | Olivia Hendrickson | 1-0-0 REC | #5051 |  |
 | Olivia Parker | 0-1-0 REC | #5241 | |
 | Olivier Aubin-Mercier | 7-5-0 UFC | #187 |  |
 | Olivier Fleurmon | 1-0-0 REC | #2193 |  |
 | Olivier Murad | 1-0-0 REC | #5636 |  |
 | Olli Santalahti | 2-3-0 REC | #3564 |  |
 | Ollie Sarwa | 5-1-0 REC | #517 | |
 | Ollie Schmid | 0-1-0 UFC | #3091 |  |
 | Olutobi Kalejaiye | 1-1-0 REC | #1732 |  |