Chris Billam-Smith stopped Tommy McCarthy to defend his European and Commonwealth cruiserweight titles on Saturday night.
Billam-Smith floored McCarthy midway through the eighth round to settle their eagerly anticipated rematch in Manchester.
It was a punishing right hook that did the damage, McCarthy crashing to the canvas face down and unable to beat the count.
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It had been an absorbing contest up to then, both men going toe-to-toe in a copybook contest to their first meeting nine months ago.
But it was Billam-Smith who largely dominated with an impressive performance.
The champion edged the opening round, jumping on the front foot from the first bell to exert some authority.
McCarthy found success at the start, and end, of the second, landing big right hands to remind Billam-Smith of his threat.
The Belfast challenger landed with the overhand right in the third but Billam-Smith soaked up any pressure as the fight started to evolve into a repeat of the first meeting.
Billam-Smith went on the attack in the fourth, landing some solid shots including one that appeared to wobble McCarthy just as he round ended.
McCarthy tried to exert some pressure in the fifth by targeting the body but was getting caught with some snappy hooks from Billam-Smith who was landing the more telling blows.
Both men appeared to be feeling the relentless pace as the sixth unfolded, with Billam-Smith sustaining a cut to his left eye after a clash of heads.
The seventh continued in the same vein, both men trading at close quarters in what was a difficult round to score.
The end arrived in the eighth, a series of close-quarter shots culminating in a big right hook that sent McCarthy to the canvas and he never looked like surviving the count.
It is McCarthy's fourth defeat as a professional and his second on the bounce against Billam-Smith.
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