British heavyweight Joe Joyce stopped Carlos Takam at Wembley Arena to move a step closer to a world title shot.
Joyce, 35, landed a series of shots in the sixth round as referee Steve Gray stepped in despite protests from Takam.
"He's a tough African lion so all credit to him. I had to take my opportunity when I saw it," Joyce said.
Joyce is now the WBO's mandatory challenger to face the winner of September's fight between Anthony Joshua and Oleksandr Usyk.
The 2016 Olympic silver medallist had not fought since inflicting a first career defeat on Daniel Dubois in November.
However, Joyce now has an impressive record of 13 wins from 13 fights, with 12 coming by knockout, and will now hope to meet Joshua or Tyson Fury in an all-British title fight.
"He's the mandatory challenger. I think providing AJ wins and Fury wins they will fight first but then they will have to fight him," promoter Frank Warren told BT Sport.
On the stoppage that angered 40-year-old Takam, Warren added: "If you're taking shots and not throwing them back the referee has no alternative, and he was not throwing shots back."
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