O’Leary’s rally reached its peak in the seventh when he trapped Chamberlain in a corner and hammered him with a body shot that sent the challenger to the canvas. Chamberlain rose slowly and survived the round, but the momentum appeared to have shifted as O’Leary continued marching forward.

The fight changed again in the tenth. Chamberlain landed a sharp combination that forced O’Leary to lower his guard before connecting with clean follow-up punches, including a straight right that sent the champion into the ropes and down. The referee waved off the contest, handing O’Leary the first defeat of his professional career while crowning Chamberlain the new IBO champion.

The victory completed a strong comeback for Chamberlain after a difficult stretch that included his lone defeat in 2024 and a draw with Jack Rafferty. For O’Leary, the loss ended an unbeaten run in what was his first defense of the title he claimed against Maxi Hughes.

Royston Barney-Smith continued his rise by defeating veteran Reece Bellotti over ten rounds to capture the vacant IBO Intercontinental junior lightweight title while retaining his WBO European belt.

The 22-year-old southpaw relied on movement, timing and accurate counter punching to frustrate Bellotti throughout the contest. Bellotti pressed forward and enjoyed moments whenever he forced Barney-Smith to the ropes, but the younger fighter consistently answered with crisp left hands and sharp combinations to earn scores of 100-90, 99-91 and 98-92.

The performance stands as the most significant victory of Barney-Smith’s career and keeps the unbeaten contender moving toward larger opportunities.

Gary Cully closed the show with one punch in an all-Irish battle against Lee Reeves that developed into one of the night’s best fights.

Reeves applied pressure from the opening bell and pushed Cully throughout the contest. Cully was deducted a point in the fifth round after repeated gumshield issues, leaving him with work to do entering the final round.

He erased any doubt 53 seconds into the tenth. Reeves walked into a perfectly timed left hand that knocked him unconscious, ending the fight instantly. Reeves was transported to a local hospital as a precaution following the knockout.

Afterward, Cully praised Reeves for forcing him into a difficult fight and said the move to junior welterweight has given new life to his career after campaigning as a lightweight.