Jack O'Brien boxer
- bouts
- 3
- won
- 0
- lost
- 3
- draw
- 0
- Status
- inactive
- Division
- -
- Debut
- 1910-10-27
- Height
- -
- Reach
- -
- Age
- -
- Born
- -
- Death
- -
- Nationality
- USA
| Date | Opponent | Last Opponents' Results | Place | Result |
|---|---|---|---|---|
| 1916-04-07 | Bobby Moore | DWWLDW | East New York A.C., Brooklyn | LOST KO |
| 1911-03-10 | Young Preston | LDLWDL | New Amsterdam Opera House, New York | LOST Technical knockout |
| 1910-10-27 | Danny McGrath | debut | Long Acre A.C., New York | LOST KO |