Chamberlain stuns O’Leary with knockout win in Dublin
Portsmouth's Mark Chamberlain knocked out Republic of Ireland's Pierce O'Leary in the 10th round in Dublin to claim the IBO light-welterweight title, handing his opponent his first professional defeat. The result was a significant statement win for Chamberlain, marking his first victory since a 2024 loss to Josh Padley and following a draw with Jack Rafferty last summer, in what was a hard-fought contest in front of O'Leary's home crowd.
Chamberlain twice floored O'Leary early on, first with a flush left hand in round one and again with a short left hook in round two, but O'Leary fought back and dropped Chamberlain with a body shot at the end of the seventh round in front of around 7,000 fans. Chamberlain recovered and eventually broke through in the 10th with a combination that sent O'Leary reeling, finishing him with a straight right that put him down for the stoppage. In the chief support, unbeaten Royston Barney-Smith outpointed Reece Bellotti over 10 rounds to win the vacant IBO intercontinental super-featherweight belt, improving his record to 17-0.
- British boxer Mark Chamberlain claims IBO light-welterweight title by 10th-round knockout of Irish challenger Pierce O'Leary in Dublin
- Chamberlain was floored in round 7 but recovered; O'Leary's first professional loss despite strong home crowd backing
- Barney-Smith extended undefeated record to 17-0 in supporting bout
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Professional boxing bouts are contested over a set number of rounds, with a knockout ending the fight when a boxer cannot continue. Titles are awarded by boxing organisations, and the IBO is one of several bodies that sanction championship belts.
Mark Chamberlain is a British boxer from Portsmouth, while Pierce O’Leary is an Irish boxer from Dublin. Their light-welterweight division has a limit of 140 pounds (about 63.5kg), and a bout in Dublin brought the title contest before O’Leary’s home crowd.