This against the game 34-year-old Brazilian Burns (19-4) who had torn through the division since moving up from lightweight. But that had caused inevitable tension at their Sanford MMA gym in Florida, and it was Usman who chose to leave for Colorado and Team Elevation under the guidance of Trevor Wittman for this fight.

“This one was a tough one, a very, very tough one, because the whole gym situation, me leaving … and first and foremost guys, you cannot discredit what Gilbert has done in this division,” Usman told Joe Rogan backstage after the fight.

“After being KO’d at lightweight, he regrouped, put it all together, moved up and started tearing through guys. We started this journey together, and he showed it tonight.

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“He’s knocked off one guy after another to get to this point, but 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 a different ball game. I’m a whole other savage from start to finish, and he saw that tonight.

“This is my cage – I’m the undisputed world champion for a reason,” Usman added. “I don’t care who you are, when you step in here there’s no friends. He said it himself, I have something he wants and he’s coming to take it, so we have to go to work.

“There was no friends in there at all. I had to go in there and win the title. I’m the best on this planet for a reason, I’m here to stay.”

There was a refusal to touch gloves before the start of the fight, with a stare-down replicating the intensity from Friday’s weigh-ins. The two also had to be separated after a feisty second round saw them go chest to chest at the bell.

It was “Durinho” who had started on the front foot, catching Usman with a huge right hand early on which wobbled him, but the champ managed to recover his composure. Burns then spent a good couple of minutes on his back trying to catch Usman with an upkick, but Usman was patiently pummelling him with big shots to the body.

Usman was fighting behind a great jab as usual, but was showing off some new tricks learned under Justin Gaethje’s coach Wittman, particularly the former interim lightweight champ’s patented leg kicks.

Burns was walking Usman down in the second round but Usman was making him respect that jab, and put him on all fours with a massive pullback right hand. Usman dropped Burns again with the jab, and Burns lay on his back again, but this time Usman motioned him back up at the behest of Wittman.

Usman looked much fresher on the stool going into the third round and it only went another 34 seconds. He switched to southpaw stance and dropped Burns again with the right jab. Keith Peterson gave Burns as much time as he could but stepped in as Usman dropped bombs on the ground.

“I knew he hits hard,” Usman told Rogan. “Funny thing is, that’s the majority of how our sparring went. If I threw one, he would counter heavy with shots and he would buzz you.

“For a lightweight who moved up, he’s got so much power. In this division, anybody else goes to sleep. He caught me in the first round with one of his big hooks, it was kinda behind the ear. [I said] let’s go to work now. The rest was history.

“Even when I first started and I was striking, a lot of that Dutch kick-boxing at my old gym, it gets you tough and it lets you see a lot of shots and defend shots. But I always get on the bag myself, and I wanted to work that southpaw.

“I knew I had a good jab from the southpaw, I love that switch, you see it in my fights. I’m mainly conventional but I like to switch stance. We worked on that this camp. Trevor said, ‘You have a freaking good jab, you need to stay on it’. I just listened to my coaches.”

Burns broke down in tears in the Octagon as his time tried to get him on his stool – understandable, given he had waited six years to get into a championship fight in the UFC.

Usman just sat a few feet away and watched intently, himself perhaps finally processing all the emotion.

After Usman’s arm was raised, they embraced and hugged, sharing some private words. The war was over, and it had never become disrespectful or boiled over into bad blood, to both men’s credit.

“It’s hard to come in without all the emotions,” Usman said. “Gilbert is a guy I’ve known from the start, and I love him. This one was tough for me to deal with.”