Dillian Whyte stopped Dereck Chisora in the 11th round of an all-British heavyweight bout at the 02 Arena on Saturday to make a claim to be Anthony Joshua's next challenger.
A largely competitive fight was instantly ended when Whyte threw a powerful left hook that left Chisora unconscious and down for worryingly long. Chisora landed heavily on his head but gradually recovered after attention from his team, potentially leaving him facing retirement at the end of a tough career.
Whyte beat Chisora on a split decision in 2016, but there was no disputing the result this time.
Chisora led on the cards of two of the three judges but left his jaw exposed and Whyte took advantage.
Whyte improved his record to 25-1 with 18 knockouts. The one loss was against Joshua in 2015 when both were on the rise.
Joshua has gone on to own the WBA, IBF, IBO and WBO titles, and his priority next year is lining up fights against WBC champion Deontay Wilder or former world champion Tyson Fury.
But Whyte appears to be the frontrunner to face Joshua, who is scheduled to return on April 13 at Wembley Stadium in London.
While Joshua believes he will crush Whyte easier in a second fight, former world champion Carl Froch believes the Olympic gold medal winner is anticipating a tough fight.
"I've never seen Chisora so motivated, so fuelled up, so fit and intense for that long. That really was a great performance," Froch told Sky Sports.
"Anthony Joshua was sitting there, looking at that closely, and he realizes that Dillian Whyte is really a stiff test for him."
Froch was very pleased with Whyte's ability to close the show with a knockout - which prevented any controversy with the scorecards.
"That's exactly what we would have not have needed," said Froch. "Anything controversial in a rematch.
"The first one was close, I had Chisora winning by a round. I had Whyte ahead there, especially with the points deduction from the referee, but it would have been close, maybe controversial.
"A finish like that is what people are going to remember."