Dereck Chisora won the vacant WBO International heavyweight title after a controversial sixth-round knockout of Malik Scott at Wembley Arena.
Chisora, who was aiming to get his career back on track after losing four of his past six fights, came through a tough contest to hand the 32-year-old Scott the first defeat of his career.
A right hand put Scott down to the canvas and, although the American seemed to be relatively unhurt as he rose at nine, the referee ruled that he did not beat the count.
It was a surprising end to a bout that seemed set to go into the later rounds, with the aggressive Chisora stalking his more fluent opponent over the course of an evenly-matched opening.
Scott tried to work the jab in the early stages but by the end of the first round he was being forced to backpedal as Chisora moved forward with swinging combinations.
The American had no qualms with fighting on the back foot, though, and began to find his range as the opening rounds wore on, becoming more and more elusive to the charging Chisroa.
But Chisora eventually managed to pounce on him, smothering his taller opponent on the ropes and knocking him down with a glancing right hand.
It certainly did not seem like a punch worthy of ending the contest, but Scott stayed on a knee until nine, and by the time he had risen the referee had ruled that the 10-count had expired.
"I knew if I caught him he was going to go down, and I caught him. I want to go back to Germany and fight Vitali again," Chisora told Box Nation.
Scott insisted he had beaten the count, saying: "I'm a professional. Dereck hit me with a good shot. I gave myself an eight-count and was up at nine."