Undisputed welterweight champion Kamaru Usman cemented his position at the top of the 170-pound division by beating top contender Gilbert Burns at UFC 258.
Usman, 33, was stunned early by the Brazilian, his former training partner.
But the Nigerian recovered superbly to turn the tables on his heavy-handed opponent, 34, and claim a third-round TKO finish at UFC Apex in Las Vegas.
He has won all 13 of his UFC fights and surpassed Georges St-Pierre for the longest winning streak at welterweight.
The two rivals were formerly team-mates at Florida gym Sanford MMA before Usman left to join Elevation Fight Team in Colorado.
After the result was announced the pair shared an embrace in the middle of the octagon, with Burns in tears and Usman appearing to fight off emotions of his own.
“This one was a tough one. It was a very, very tough one, because of the whole gym situation (and) me leaving,” Usman said after his third straight UFC title defence.
“But I’ve said it, man, I’m the varsity guy. My fight IQ is different. It’s different when you’re in the gym with me. But when you get in here, it’s different ball game. From start to finish, I’m a whole other savage, and he saw that tonight.
“So, from start to finish there was no friends in there, no friends at all. I had to go in there and do what I had to do, and that’s go in and win this title. I am the best on the planet for a reason (and) I’m here to stay.”
Usman’s victory ended Burns’ six-fight winning streak, extended his own winning run to 17 consecutive fights and improved his mixed martial arts career record to 18 wins and one loss.
After the fight he called for a rematch with Jorge Masvidal, who he beat at UFC 251, adding: “He keeps running his mouth. If he’s going to talk, step in here and see me.”