Casey O'Neill

Casey “King” O’Neill is the most exciting female fighter in Australian MMA, and the fact that a torn knee could not derail her career tells you everything about the competitive fury that burns inside this Queensland-based Scotswoman. Born on October 7, 1997, in Scotland, O’Neill moved to Australia as a teenager, adopted the country as her own, and has represented Australian MMA with a ferocity that would make any patriot proud.

O’Neill burst onto the UFC scene with four consecutive victories that announced her as the real deal — aggressive striking, improving grappling, and a refusal to take a backward step that made her immediately dangerous at women’s flyweight. Then came the knee injury that required surgery and the kind of rehabilitation that tests mental strength as much as physical resilience. Her comeback at UFC 305 in Perth in August 2024 — a unanimous decision over Luana Santos — was a statement: “King” is not a nickname; it is a declaration of intent.

Ranked eleventh in the UFC Women’s Flyweight division as of September 2025 with a record of 10-2, O’Neill has a bout scheduled against Gabriella Fernandes and remains one of Australia’s best hopes for a female UFC champion. She is 28, her best fights are ahead of her, and the combination of youth, talent, and the kind of determination that injuries only sharpen makes her a future title contender. Australian MMA fans should be paying very close attention.

Fight Record

Fighter Profile

Casey O’Neill competes in the Women’s Flyweight division with 7 wins from 9 UFC appearances and a 10-2 professional record that reflects both her talent and her ability to overcome adversity. The Queensland-based fighter is ranked eleventh and building towards a future title challenge with the kind of aggressive, no-retreat fighting style that Australian fans love. The crown is not hers yet. The intent is unmistakable.

VS — Chief sports columnist, australiafootball.com