Sean O'Brien History
| Club | Country | Position | NO | From | To |
|---|---|---|---|---|---|
| Ireland U20 | Ireland | Blindside Flanker | 01/01/2020 | 01/04/2021 | |
| Leinster | Ireland | Openside Flanker | 01/01/2021 | 01/06/2021 | |
| LA Giltinis | United States | Openside Flanker | 01/06/2021 | 01/04/2022 | |
| Leinster | Ireland | Openside Flanker | 01/04/2022 |
NO = Player number .