Anthony Joshua defended his IBF heavyweight title by knocking out Dominic Breazeale in the seventh round Saturday, ending his American challenger's unbeaten record.
It was only the second time in the 26-year-old Joshua's career than he has required more than three rounds to see off an opponent.
A devastating left-right combination, similar to those that stopped many of the Briton's 16 previous opponents, sent Breazeale to the canvas so heavily it appeared the fight was over early in the seventh round.
Breazeale returned to his feet, clinging to the last seconds of his undefeated professional record, before a further barrage dropped him again.
It left the referee with little choice but to wave the action over, one minute and one second into the seventh round at London's O2 Arena.
Joshua was patient throughout the opening round, frequently landing left jabs and the occasional hurtful right, even showing a previously-unseen head movement to evade a Breazeale counter.
In the second Joshua displayed greater aggression. He punched through Breazeale's high guard, and repeatedly sought — and often successfully found — his opponent's resistant head with uppercuts, left hooks and straight rights. Significant swelling was already appearing around Breazeale's right eye.
What followed was a demonstration of Joshua's relish of combat. Breazeale's impressive punch resistance ensured he remained on his feet, and when he fought back and landed, Joshua responded with greater malice.
His inexperience showed at one point with punches that missed wildly, while Breazeale continued to absorb heavy punishment in the rounds that followed, particularly a perfectly-timed left hook midway through the fifth.
The most impressive performance of Joshua's career culminated with that combination in the seventh, and he clinically finished.
"It was a matter of timing and a process," Joshua told British broadcaster Sky Sports. "I only had two weeks off after my last fight (against Charles Martin in April) and now I want to have a nice bit of time off."
It is expected he will next face mandatory challenger Joseph Parker of New Zealand
Joshua is adjusting his plans after Tyson Fury was forced to postpone his rematch with Wladimir Klitschko after hurting his left ankle in training.
"I was looking at Tyson Fury and I hope he gets better soon because I was hoping to get that in the winter," Joshua said. "In the meantime, we'll look at other opponents like Joseph Parker."