Jack O'Brien boxer
- bouts
- 1
- won
- 1
- lost
- 0
- draw
- 0
- Status
- inactive
- Division
- lightweight
- Debut
- 1899-02-10
- Height
- -
- Reach
- -
- Age
- -
- Born
- -
- Death
- -
- Nationality
- USA
| Date | Opponent | Last Opponents' Results | Place | Result |
|---|---|---|---|---|
| 1899-02-10 | John Farrell | debut | Teutonia Hall, San Francisco | WIN KO |
