Jack O'Brien (Denver Jack O'Brian) boxeur
- combats
- 7
- gagnés
- 1
- perdus
- 3
- match nul
- 3
- Situation
- inactive
- Division
- middleweight
- Début
- 1919-11-26
- Taille
- -
- Allonge
- -
- âge
- -
- Né
- -
- Décès
- -
- Nationalité
- USA
| Date | Adversaire | Derniers résultats des adversaires | Lieu | Result |
|---|---|---|---|---|
| 1921-09-30 | Joe Black | DLWWLD | Stockyards Stadium, Denver | WIN |
| 1921-09-09 | Harry Reide | LDDDDW | Stockyards Stadium, Denver | DRAW Points |
| 1921-06-21 | Harry Reide | WLDDLD | Stockyards Stadium, Denver | DRAW Points |
| 1921-06-03 | George Eagel | DLWWDD | Jazzland Theatre, Casper | LOST Technical knockout |
| 1921-05-20 | Billy Williams | debut | Jazzland Theatre, Casper | DRAW Points |
| 1920-01-01 | Walter Caldwell | WW | Crystal Theater, Albuquerque | LOST Technical knockout |
| 1919-11-26 | Mack Dalton | D | Salt Lake City | LOST Technical knockout |