Casey O'Neill Record: 11-2-0
FlyweightCasey O'Neill has a 11-2-0 professional record and is 28 years old in the Flyweight division, representing Xtreme Couture. This profile tracks fight history, UFC stats, ELO rating, record, age, and opponent links.
Last updated Jun 19, 2026 · Combat Edge fight database
Casey O'Neill bio
Personal background
Casey O'Neill, the UFC women's flyweight known as "King," is a Scottish-Australian fighter born on October 7, 1997, in Irvine, Scotland. Combat sports were in her blood from the start: her father, Cam, was a professional kickboxer, and she began training in kickboxing at the age of four. When she was 10 the family relocated to Australia's Gold Coast, where her father later started his own MMA promotion and where she added Brazilian jiu-jitsu to her game as a teenager. Listed at 5'6" with a 69-inch reach, O'Neill built her UFC run training out of Xtreme Couture in Las Vegas, blending the striking she grew up with and a well-rounded grappling base into the aggressive, all-action style that earned her the "King" moniker. She carries an 11-2 record in the flyweight division.
Path to the UFC
O'Neill turned professional in 2019 and overwhelmed the Australian regional scene, going unbeaten in promotions like Eternal MMA with a mix of decisions, a rear-naked choke and knockouts, including a 2020 KO of Christina Stelliou at UAE Warriors. That perfect start – eight straight wins before reaching the UFC – made her one of the most hyped flyweight prospects in the world when she signed with the promotion.
Fast start in the Octagon
O'Neill debuted in February 2021 with a second-round TKO of Shana Dobson, then submitted Lara Fritzen to keep her unbeaten run intact. The breakout came in October 2021, when she stopped Antonina Shevchenko by second-round TKO, a statement win over a ranked opponent. She pushed to 11-0 in February 2022 with a split-decision victory over former title challenger Roxanne Modafferi at UFC 271, cementing herself as a genuine contender in her early twenties.
Adversity and the road back
The undefeated run ended in March 2023 at UFC 286, where Jennifer Maia handed O'Neill her first professional loss by unanimous decision. She suffered a second setback that December at UFC 296, tapping to an armbar against Ariane Lipski da Silva. O'Neill steadied herself in August 2024 at UFC 305, out-pointing rising Luana Santos over three rounds, then returned in March 2026 to stop Gabriella Fernandes with first-round punches, reasserting the finishing edge that defined her early career.
Fighting style
O'Neill is one of the more versatile fighters at 125 pounds, with a balanced 11-2 record that splits four knockouts, two submissions and five decisions for a 55% finish rate. Raised on kickboxing and rounded out with jiu-jitsu, she pushes a high pace, mixes levels well and is comfortable winning either on the feet or by grinding out rounds. Her two losses revealed the areas to tighten – defensive grappling against an experienced submission artist in Lipski, and consistency over 15 minutes against a savvy veteran in Maia – but her recent finishes show a fighter who has folded those lessons back into a still-improving, well-rounded game.
Career highlights
- 11-0 start to her career — opened with eleven straight wins, including UFC victories over Antonina Shevchenko and former title challenger Roxanne Modafferi.
- Ranked-opponent breakout — stopped Shana Dobson on debut and built a top-15 flyweight resume in her early twenties.
- Resilient comeback — answered back-to-back losses with wins over Luana Santos and a first-round finish of Gabriella Fernandes.
Casey O'Neill career snapshot
Casey O'Neill quick answers
What is Casey O'Neill's record?
Casey O'Neill's professional MMA record is 11-2-0.
How old is Casey O'Neill?
Casey O'Neill is 28 years old.
What weight class is Casey O'Neill?
Casey O'Neill fights at Flyweight in UFC.
How tall is Casey O'Neill?
Casey O'Neill is 5'6" tall with a 69" reach.
How much does Casey O'Neill weigh?
Casey O'Neill competes at Flyweight, with a most recent weigh-in of 125 lbs.
What is Casey O'Neill's Combat Edge Elo?
Casey O'Neill's Combat Edge Elo is 1682, with a peak Elo of 1716.
How strong is Casey O'Neill's recent opposition?
Casey O'Neill's latest 10 counted opponents averaged 1595 Elo immediately before their fights. This avoids using opponents' later career results with hindsight.
When was Casey O'Neill's last fight?
Casey O'Neill's latest tracked pro fight was against Gabriella Fernandes at UFC Fight Night on Mar 28 2026.
What is Casey O'Neill's recent form?
Casey O'Neill's recent tracked pro form is W-W-L-L-W over the latest 5 decisive pro results.
How does Casey O'Neill usually win?
Casey O'Neill's 11 recorded wins include 4 knockouts, 2 submissions, and 5 decisions, with 55% ending before the final bell.
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