It will be nearly three years on Saturday when Kamaru Usman faces Khamzat Chimaev in the co-main event of UFC 294 at Etihad Arena in Abu Dhabi, United Arab Emirates, that he's fought anyone other than Leon Edwards.

Usman was training as normal last week when he was called asking if he'd be available, if needed, for UFC 294. Paulo Costa was supposed to fight Chimaev, but he had surgery on his right elbow that developed into a staph infection, forcing him out.

Usman said he couldn't think of any reason why he shouldn't take the fight with Chimaev, even though it would be up a weight class at middleweight. He called his manager and his coaches and they had no issues with it, either, even though he'd be taking the bout on 10 days' notice.

He's entering the bout on a two-fight losing streak, and is a fairly significant underdog to Chimaev. At BetMGM, Chimaev is -280 to win, with Usman at +230.

"I've been asked that [about being on a two-fight losing streak] a few times, and I'm starting to think about it now," Usman told Yahoo Sports, laughing. "I didn't really think about that, or anything else. They just said, 'Hey, do you want to fight this kid?' And I was like, 'Yeah, I do want to fight the kid. But you want me to go up a weight class to fight him on 10 days' notice? OK. Let's do it.' I didn't give [the back-to-back losses to Edwards] a thought. I saw an opportunity and I decided to go for it.

"Some guys will sit at home and they've been doing nothing and a huge opportunity comes, they can't capitalize on it because they're not prepared. For me, in a sense, I've been preparing. It's not like I was sitting at home doing nothing. I was working, trying to get better, trying to learn new things. When this came up, I could take it because I had been working. I called my coaches right away and they didn't talk me out of it, so I was ready to go. I never for a minute thought about having those [losses] on my record."

When he was welterweight champion, Usman saw Chimaev's early fights in the UFC and believed they'd meet some day.

Chimaev created a frenzy in 2020, winning two bouts in 10 days in Abu Dhabi in almost the most dominant way imaginable. He then came to the U.S. two months later and knocked out veteran middleweight Gerald Meerschaert in 17 seconds.

He was the talk of the sport.

"He was doing what he was supposed to do with the opposition he was presented with, and I have to give him credit for that," Usman said. "He got a lot of attention at the time he was doing it because the world was starving for that. Nothing was going on in the world and people were looking for entertainment. And here's this big, strong scary-looking kid going out and taking fighters and absolutely destroying them. At that time, wow, how could you not be impressed?"

The Chimaev hype train is still running, though it has slowed considerably. Injuries and COVID-19 kept him out for 13 months, until he choked Li Jingliang unconscious at UFC 267 in Abu Dhabi, talking to UFC CEO Dana White seated ringside while he was in the process of pummeling Jingliang.

It was another six months until Chimaev fought Gilbert Burns. And while he won, and proved himself worthy of the hype, for the first time, he had to dig deep.

Usman was impressed by what he saw given his relationship with Burns, and he was convinced they'd meet at some point.

"He has a win over Gilbert, and how can you not be impressed by that?" Usman said. "Gilbert is a bad dude. But I think Khamzat realized after that fight he wasn't going to run over everyone like he had been."

When Usman was formally asked to replace Costa in a bout against Chimaev, he never for a minute thought it would be easy. He knew that Chimaev would test him in every phase of the game.

But he was confident because despite the losses to Edwards — they fought three times, with Usman winning the first and Edwards taking the last two — that he's continued to evolve as a fighter.

And knowing he has a win over Sean Strickland, the middleweight champion, and will get a title shot if he beats Chimaev, he couldn't say no.

"This sport is crazy, man," Usman said. "Did I ever think I'd be sitting here talking to you after losing [back-to-back fights] to Leon? Nah, man. No way. Our second fight, I was seconds away from winning it and Leon landed that kick that changed history. And the third fight, I'm still not sure, but I just wasn't where I wanted to be. Leon obviously is a very good fighter and deserves credit, but that night, I wasn't there like I usually was or needed to be.

"When that happens, what do you do? I went back to the gym and got to work. I made myself better. Now, I know I am better and that made it easy to take the fight. I didn't even think about the losses until guys started asking me about it. I feel great and I'm ready to go out there and do me."