Briton Mark Chamberlain stunned Republic of Ireland’s Pierce O’Leary as he dropped him twice on the way to securing a knockout win in the 10th round to claim the IBO light-welterweight belt.

Chamberlain had to climb off the canvas himself in the seventh round as O’Leary struck him with a ferocious body shot in front of a capacity crowd in Dublin.

But just as momentum appeared to be swinging in the favour of O’Leary, Chamberlain found a breakthrough and managed to get the stoppage late on.

Portsmouth’s Chamberlain now moves to 18 wins with one defeat, bouncing back to winning ways for the first time since losing to Josh Padley in 2024.

This was Chamberlain’s first fight since he drew with Jack Rafferty in Altrincham last summer.

“First of all respect to Pierce for giving me this opportunity,” Chamberlain told DAZN after the fight.

“I’m not a stranger to an away day and anyone that knows me knows that I will fight anyone and if that means that I have to go into the champions’ back garden then I will do that.

“I’ve never been hurt before in a fight but that body shot stopped me in my tracks but fortunately I was able to get thorugh it and weather the storm.

“We’ve been working on new things in the gym and it’s all paid off, I asked Frank (Warren) in the dressing room before the fight if we could bring a show down to Portsmouth, I’d love that. “

After a tight and cagey first round, Chamberlain stunned the home crowd of around 7,000 as he landed a flush left hand that sent O’Leary flying back onto the canvas.

Chamberlain then found another big shot in the next round as he sent his opponent to the floor again with a short left hook.

But O’Leary responded well to the knockdowns, rallied by his home crowd as he pressed on to find a way back into the fight.

He then found a breakthrough at the end of the seventh round as he backed Chamberlain into a corner and sent a punishing shot into his chest.

Chamberlain was slow to get to his feet but survived the count and managed to avoid major punishment before the bell sounded.

O’Leary continued to press on, with Chamberlain looking tired and the Irishman buoyed by the crowd.

But Chamberlain struck in the 10th with a combination that saw O’Leary drop his hands and then pressed on, landing a number of clean shots that included a straight right hand to send O’Leary tumbling into the ropes and to the canvas.

Fight promoter Frank Warren revealed after the fight that there is a rematch clause in the fight contract that could see the pair fight again in the near future.