Tony Bellew has beaten David Haye by an 11th-round technical knockout in their heavyweight showdown at London's O2 Arena.
The grudge match got off to a ferocious start, but things went badly for Haye from the sixth round when, after losing his balance, he suffered an apparent Achilles injury that meant he could barely stay on his feet.
The 36-year-old Haye has fought less than three rounds in almost five years.
On the verge of exhaustion, he persisted bravely until the 11th round, when Bellew hit him down to the floor and the older fighter fell out of the ring.
He climbed back in, but his corner threw in the towel.
Bellew, the WBC cruiserweight champion, showed patience in picking his moment to finish off Haye.
The sensational win follows a blistering war of words between the contenders in the build up to the match.
But for all of his bravado in the build-up, Haye was sometimes tentative on the night, often appearing reluctant to throw punches because of Bellew's superior speed.
After the bout the two embraced, with Bellew paying tribute to Haye.
Haye likewise praised his opponent after the match, and refused to blame his injury for his defeat.