Casey O'Neill vs Eduarda Moura Prediction & Fight Preview - 9/19/2026
Updated September 19, 2026
Updated September 19, 2026
Casey O'Neill and Eduarda Moura meet in a ranked women’s flyweight matchup at UFC 331 on Saturday, September 19, 2026, at Crypto.com Arena in Los Angeles, with both fighters trying to move closer to the division’s top 10. O'Neill returned from an extended absence in March with a first-round knockout of Gabriella Fernandes, while Moura is attempting to rebound from a unanimous decision loss to Wang Cong in February. Polymarket has made O'Neill the favorite going into this fight, which is the only women's matchup on this card.
Why Our Model Sees Value:
“Moura’s grappling gives her a credible route to controlling portions of the fight, but the current price does not fully account for the gap in striking volume, O'Neill’s reach advantage, and O'Neill’s ability to force Moura to work much harder whenever the fight stays standing.”
O'Neill Not Favored By Enough
Polymarket currently prices O'Neill at approximately 68¢, compared with 33¢ for Moura, giving the Australian an implied win probability of 68%. More than $13,000 has been traded across the market, so this is not an empty early line with little participation behind it. Still, a 68¢ price leaves enough room for a prediction if O'Neill’s true probability is in the low-70% range.
Striking Volume Favors O'Neill
The case for O'Neill centers on where most of the fight is likely to be spent. Her career UFC numbers show 7.89 significant strikes landed per minute, while Moura lands only 2.57. O'Neill is certainly hittable herself, absorbing 5.53 significant strikes per minute, but Moura has never established herself as a high-volume striker who is likely to exploit that weakness consistently.
Recommended Prediction:
O'Neill to Win
Current Market Price:
68¢
Model Win Probability:
72%
Market-Implied Probability:
68%
Model Edge:
4%
Buy Up To:
70¢
Model Trade Confidence:
71/100
Fighter | Age | Height | Reach | Stance | Record |
|---|---|---|---|---|---|
Casey O'Neill | 28 | 5'6" | 69" | Orthodox | 11-2 |
Eduarda Moura | 32 | 5'6" | 67" | Orthodox | 12-2 |
O'Neill enters UFC 331 on a two-fight winning streak. She defeated Luana Santos by unanimous decision at UFC 305 before spending roughly 19 months away from competition. Her return against Gabriella Fernandes in March could hardly have gone better. O'Neill hurt Fernandes with a counter left hand and followed with a sustained attack that forced the stoppage at 3:11 of the opening round. It improved her professional record to 11-2 and UFC record to 6-2.
Moura is 3-2 across her first five UFC appearances. After a split-decision loss to Denise Gomes, she moved to flyweight and defeated Veronica Hardy and Lauren Murphy by unanimous decision. Her run was stopped by Wang Cong in February. Cong dropped Moura in the opening round and controlled most of the striking exchanges, although Moura answered with a strong second round on the ground and threatened with a rear-naked choke. Cong regained control in the third to earn scores of 30-27, 29-28 and 29-28.
This is where O'Neill has her biggest statistical advantage. She lands 7.89 significant strikes per minute at roughly 52% accuracy. Moura lands 2.57 per minute and has connected on 183 of 485 significant-strike attempts in her UFC career. O'Neill also owns a two-inch reach advantage based on available measurements.
O'Neill is most effective when she can build combinations and make exchanges increasingly uncomfortable for her opponent. Her defense is not airtight, but she generates enough offense to make opponents pay for giving her extended time at boxing range. The Fernandes finish also showed that she can capitalize quickly when an opponent is hurt rather than simply accumulating volume.
Moura is less interested in producing extended high-volume kickboxing exchanges. Her striking serves as a route into physical clinches and grappling sequences, and 34% of her recorded significant strikes have come on the ground. Allowing O'Neill to establish her preferred pace from range would make Moura’s job significantly harder.
Moura’s best chance to change the fight is through her wrestling and top control. She averages 3.58 takedowns per 15 minutes and has five career submission wins. She was able to control large sections of the second round against Cong and came close to completing a rear-naked choke against a strong opponent.
O'Neill owns 70% takedown defense and averages 1.4 takedowns of her own per 15 minutes. Those numbers do not make Moura’s wrestling irrelevant. In fact, they are the primary reason the model stops well short of treating O'Neill as an overwhelming favorite. Moura could win rounds simply by putting O'Neill on her back and keeping her there.
The question is whether Moura can repeat that process often enough across three rounds. Failed takedowns and difficult clinch sequences consume energy, and O'Neill’s activity can quickly build a statistical advantage once the fighters separate.
Expect Moura to have success getting the fight into grappling situations at least once, particularly during the opening 10 minutes. Her physical strength, takedown activity and submission background make a completely clean striking match unlikely for O'Neill.
Over the full 15 minutes, however, O'Neill has more ways to consistently bank rounds. She should land at a higher rate whenever there is space, and her reach gives her another small advantage in exchanges. Moura may produce the most dominant individual stretches through top control, but O'Neill is more likely to win a greater share of the total minutes.
My prediction is Casey O'Neill to win, with a decision the most likely individual result. Her recent form, major striking-volume advantage and ability to make Moura pay between grappling exchanges support a model probability of 72%. At the current 68¢ Polymarket price, that leaves a modest but usable 4% edge.