Casey O'NeillW vs. Eduarda Moura
UFC 331 · September 19, 2026 · Crypto.com Arena · Early Prelims 5:30 PM ET
The brief
- The result
- Casey O'Neill by Submission (armbar), R1
- What kind of fight
- Ranked flyweight crossroads fight
- Finish likelihood
- Medium
- The line
- O'Neill -200 · Moura +165Consensus (multiple sportsbooks)
- The stakes
- Flyweight · Early Prelims
The result
Casey O'Neill def. Eduarda Moura — Submission (armbar), R1 3:22
Casey O'Neill survived early trouble and finished Eduarda Moura with a spectacular armbar at 3:22 of the first round.
Moura scored a takedown and had O'Neill in danger with a tight anaconda-choke attempt, but O'Neill worked free, put both feet on Moura's hips to elevate her, and rolled the scramble straight into the fight-ending submission.
The breakdown below was written before the fight.
The read
O'Neill's momentum and finishing power make her the pick, but Moura's grappling pedigree and five submission wins mean any scramble is dangerous for the Australian.
If O'Neill can keep this standing behind her power, she should find another finish; if Moura gets this to the mat, her submission threat is live in every position.
A close, competitive fight either way.
The matchup
This is a genuine top-15 flyweight matchup between two ranked contenders coming off different results.
O'Neill's power and well-rounded game were on full display in her comeback knockout of Gabriella Fernandes, while Moura's submission craft has been enough to beat a former title challenger even as she dropped her most recent decision.
Whoever wins likely moves closer to the division's contender picture.
Tale of the tape
| 11-2 | Record | 12-2 |
| 28 | Age | 32 |
| 5'6" | Height | 5'6" |
| — | Reach | — |
| — | Stance | — |
| Australia | Country | Brazil |
| — | Team | Galpão da Luta |
The numbers
Career UFC averages. Red bar = statistical edge.
The fighters
Casey O'Neill 11-2
“King”
Casey O'Neill is a 28-year-old flyweight fighting out of Queensland, Australia and currently ranked No. 12 in the division. She returned from more than a year away from competition with a first-round knockout of Gabriella Fernandes in March 2026, and now meets fellow ranked contender Eduarda Moura in a bout that could shake up the top 15.
- WGabriella Fernandes · KO/TKOUFC Fight Night: Adesanya vs. Pyfer · March 28, 2026
Eduarda Moura 12-2
“Ronda”
Eduarda "Ronda" Moura is a 32-year-old Brazilian flyweight training at Galpão da Luta, currently ranked No. 13 in the division. She is coming off a decision loss to Cong Wang in February 2026 that snapped a two-fight winning streak that included a win over former title challenger Lauren Murphy. She now meets fellow ranked contender Casey O'Neill in Los Angeles.
- LCong Wang · Decision (unanimous)UFC Fight Night · February 7, 2026
- WLauren Murphy · Decision (unanimous)UFC on ESPN · July 12, 2025
- WVeronica Hardy · Decision (unanimous)UFC 309 · November 16, 2024