Mark Chamberlain secured a 10th-round knockout victory against Pierce O’Leary in Dublin, claiming the IBO light-welterweight belt after recovering from a seventh-round knockdown in front of a capacity crowd of around 7,000.
The 10th-round stoppage brought a dramatic end to a high-stakes clash in Dublin, where Mark Chamberlain entered hostile territory as the B-side and underdog against Republic of Ireland’s Pierce O’Leary. Fighting before an amped-up audience at 3Arena, the Portsmouth boxer shook the arena early before weathering a severe middle-round crisis to capture the IBO light-welterweight belt.
Early Knockdowns Stun the Dublin Crowd
Following a tight and cagey opening frame, Chamberlain stunned the home crowd of around 7,000 when he landed a flush left hand that sent O’Leary flying back onto the canvas. The English fighter pressed his advantage into the next round, finding another big shot that dropped his opponent to the floor again with a short left hook. Those early exchanges left O’Leary’s nose likely broken as it poured blood for the remainder of the fight.
Despite walking into hostile turf as the underdog, Chamberlain fed off the electrified atmosphere. The early success pushed his record to 18 wins with one defeat, bouncing back to winning ways for the first time since losing to Josh Padley in 2024.
O’Leary’s Body-Shot Rally and the Seventh-Round Drama
O’Leary did not throw in the towel after falling behind on the judges’ cards. Buoyed by the local supporters, the Dublin native rallied through the middle rounds, pressing forward and doing significant damage with punishing work to the body.
That aggression paid off in the seventh round. O’Leary trapped Chamberlain into a corner and unloaded a ferocious body shot that dropped the Englishman heavily to the canvas. Chamberlain was slow to get to his feet, barely beating the count as the bell approached to survive the round.
The 10th-Round Stoppage and Decisive Finish
As the fight entered the championship rounds, Chamberlain looked visibly tired while O’Leary continued to press forward. Yet, just as momentum seemed firmly in the Irishman’s corner, the visitor found a late breakthrough in the 10th round.
Chamberlain uncorked a sharp combination that forced O’Leary to drop his hands, allowing the English challenger to land a flurry of clean punches. A straight right hand sent O’Leary tumbling into the ropes and down to the canvas, prompting the referee to step in and halt the contest.
Where Both Fighters Stand After the Dublin Thriller
The thrilling encounter proved a stark test of resilience for both athletes. Chamberlain entered the bout following a draw with Jack Rafferty in Altrincham last summer, but now leaves Ireland with the IBO title and an 18-1-1 professional record boasting 13 knockouts.
