Come Saturday night, and the headline bout on the UFC 258 card at the Apex facility in Las Vegas, and Usman (17-1) will defend his welterweight title against Burns (19-3), who he has known since their training days together began at Florida’s Sanford MMA in 2013.

Back then, Burns had just emerged from Brazil as a former world BJJ champion and as a lightweight MMA prospect. Now the 34-year-old has designs on the welterweight belt “The Nigerian Nightmare” won in 2019, and has defended twice in quite devastating fashion.

A positive Covid-19 test last July meant Burns was withdrawn from his first scheduled date with this particular piece of destiny. Usman says the extra time has simply sharpened his focus.

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“I’ve had so much more time to soak in the thought of what I have to go out there and do,” says Usman, speaking to SCMP MMA from Las Vegas “This has been a lot better, [I’m] a lot more comfortable with the thought of going out there and beating up a former teammate.

“People forget he’s only been a welterweight for less than two years. So training with him back to 2013, I never really thought we’d embark on this one. So I never held anything back, in terms of helping him, thinking we might fight one day.

“But it’s true I did [hold back] in terms of not hurting my training partner. Nobody wants to train with you if you’re killing them every day.”

In the lead-up to that proposed bout last July, Usman shifted fight camp to Colorado, under the command of Trevor Wittman. And he continued there in the lead-up to this weekend.

“It’s been really good,” he says. “As human beings we don’t necessarily like change. But I love working with Trevor. With new training partners you never know what you’re going to get. You have to go in there and work that out. That’s where the extra heartbeat comes from.

“You walk in and you feel certain energies. You have to find a way to break the ice, and to fit in. But to walk into Trevor’s gym and work with someone like [No 2-ranked lightweight] Justin Gaethje. To see [former strawweight champ] Rose Namajunas train. These guys are so good. I get the privilege to watch how they train.”

The instant result of the change in scenery was seen last time out, when Usman took on Jorge Masvidal (35-14) at UFC 251 last July, and monstered the American over five rounds in a one-sided affair. As with Usman’s first title defence – when he broke fellow American Colby Covington (16-2) down and he broke his jaw – it was a reminder of just how complete a fighter the former wrestling stand-out has become.

But the work continues every day, says Usman.

“It’s a weird position to be in,” he says. “You’re constantly worried there’s somebody out there in the world that’s working, right now. For years I took the approach that I wanted to work harder than everybody. Then when you get to the top, there’s this sense you need to take some time off because you’ve been running your body crazy. But you can’t because you feel guilty, you feel there’s someone else … they’re coming for me.

“It’s not enjoyable, it’s not rest and recover, it’s still out there working and thinking. So you watch and chart the evolution of these other fighters, the ones who are closing the gap or at least learning new skills.”

Fight week has seen many attempts to draw Usman into thinking beyond Burns and to his growing legacy as a welterweight who has so far – at 12-0 with the UFC – answered everything that’s been asked of him inside the cage. Outside the cage he seems to have all bases covered, too.

“I try not to look beyond the task at hand,” he says. “If you look too far into the future you might trip over what’s in front of you. So I try to hone in on what’s in front of me, which is Gilbert Burns. This is the toughest test today, and we’re paying attention to this.”