Nicknamed King
O'Neill goes by the nickname "King".
MMAUFCWomen's FlyweightOrthodox
Casey O'Neill
AustraliaAge, record and fight historyCasey O'Neill represents Australia in the UFC, where she has fought at Women's Flyweight since 2021.
14pro fights9UFC fights
Updated
About Casey O'Neill
Casey O'Neill was born on October 7, 1997, in Irvine, Scotland, and represents Australia. Her professional career began in 2019, and she has fought at Women's Flyweight in the UFC since 2021. She fights from the orthodox stance, out of Las Vegas, Nevada, United States, and holds a brown belt in Brazilian Jiu-Jitsu under Casey Halstead. O'Neill has trained at Fight Ready since 2024.
Agatha Research DeskUpdated Oct 5, 2026Fight history9
Every UFC fight in our records, newest first.
| Date | Event | Opponent | Result | Method | Rd | Time |
|---|---|---|---|---|---|---|
| Sep 19, 2026 | UFC 331: Van vs. Pantoja 2 | Eduarda Moura | W | Submission | 1 | 3:22 |
| Mar 28, 2026 | UFC Fight Night: Adesanya vs. Pyfer | Gabriella Fernandes | W | KO/TKO | 1 | 3:11 |
| Aug 17, 2024 | UFC 305: Du Plessis vs. Adesanya | Luana Santos | W | Decision (unanimous) | 3 | 5:00 |
| Dec 16, 2023 | UFC 296: Edwards vs. Covington | Ariane da Silva | L | Submission | 2 | 1:18 |
| Mar 18, 2023 | UFC 286: Edwards vs. Usman 3 | Jennifer Maia | L | Decision (unanimous) | 3 | 5:00 |
| Feb 12, 2022 | UFC 271: Adesanya vs. Whittaker 2 | Roxanne Modafferi | W | Decision (split) | 3 | 5:00 |
| Oct 2, 2021 | UFC Fight Night: Santos vs. Walker | Antonina Shevchenko | W | KO/TKO | 2 | 4:47 |
| Jun 19, 2021 | UFC Fight Night: Jung vs. Ige | Lara Procopio | W | Submission | 3 | 2:54 |
| Feb 20, 2021 | UFC Fight Night: Blaydes vs. Lewis | Shana Dobson | W | KO/TKO | 2 | 3:41 |
How she is doing now
UFC record7-29 fights since 2021
Pro record12-2-014 pro fights
Last fightSep 19beat Eduarda Moura
Last 53-2WWWLLNewest first. Three wins in a row.
Did you know?!
First UFC fight by KO
In her first UFC fight, O'Neill beat Shana Dobson by KO/TKO in round 2 at 3:41 at UFC Fight Night: Blaydes vs. Lewis on Feb 20, 2021.
Career
7years2019 to 2026
- 2021UFC debutBeat Shana Dobson
- Sep 19, 2026Latest fightBeat Eduarda Moura
How his UFC fights ended
7 wins
KO/TKO 3Submission 2Decision 2
2 losses
Submission 1Decision 1
Divisions
- Women's Flyweight: 7-22021 to 2026, 9 UFC fights
First UFC fight
Feb 20, 2021: beat Shana Dobson by KO/TKOFight Night: Blaydes vs. Lewis, round 2, 3:41
Latest fight
Sep 19, 2026: beat Eduarda Moura by submissionUFC 331: Van vs. Pantoja 2, round 1, 3:22
Sources and updates
Fights, records and schedules come from Agatha's own records: ESPN's fighter records and results, and the UFC fight history in our data.
Updated Oct 5, 2026, 3:18 PM ET. Results and form refresh after every fight; biography facts are checked weekly.