NEW YORK — Because his heavyweight title fight with Daniel Cormier came together under pressured circumstances to save UFC 230, Derrick Lewis’s improbable rise has gone woefully understated. An ex-convict who did time at the Central Unit in Sugar Land after a harsh childhood in Louisiana, Lewis has the kind of triumphant story that only the fight game can tell — a reversal of fortunes so complete that his past life barely registers as real.

Lewis was teetering on becoming a forgotten soul, and now here he is fighting for the heavyweight title. It’s been a crazy ride.

He debuted in 2014 against Jack May to kick off a UFC on FOX card in Orlando. You could hear him pound the canvas up from up in the nose bleeds when he finished May in the first round, and the roar he let out was immediately understandable given where he’d come from. I wrote a feature about him that same year ahead of his second UFC fight with Guto Inocente. And even then it felt like he was nearing the high-water mark of his career, given that he was competing in the UFC’s most merciless division. It felt like if you were going to do a Derrick Lewis feature, it had better be while he was still on the roster.

Yet who could have known that four years later “The Black Beast” — who has since become a master of the incredibly timed un-PC joke — would be fighting for a title? At Madison Square Garden? Riding a streak where he has won nine out of 10 fights, and carrying with him an endorsement contract with Popeye’s Chicken?

Could Lewis himself have even dreamed that he would end up in such a fortuitous set of circumstances — on the strength of his own perseverance and will — while he was watching time slip away from him in Sugar Land? The answer isn’t exactly no, but he’s taking everything in stride.

“Before I got into the UFC, I was telling people and the local media that I would be in the UFC in two years, and I got into the UFC two years into my career,” Lewis told MMA Fighting before the media day in Manhattan. “Then I told them I would be champ, that when I do get in the UFC I’d be champ within two years. It didn’t take two years, it took four years before I got the opportunity, but I’m here.”

Even as he gets set to try and dethrone Cormier for the heavyweight title, there’s a healthy amount of “how in the hell did we get here?” in the New York air. Lewis was booked to face the future of the division, Francis Ngannou, at UFC 226 back in July. Ngannou, having come off his first loss against Stipe Miocic, was raring to get back on track, and Lewis was — in the minds of many — an obstacle in his way.

So what happened? Lewis won a decision in perhaps the most bizarrely contested fight of the year. Bizarre because Ngannou was reluctant to engage, and Lewis was dealing with back issues that prevented him from pushing the action the other way. It played out like a super suspenseful game of caution. Lewis just happened to do more, and he was the one who got his hand raised.

In his next fight, against Alexander Volkov on Oct. 6 at UFC 229, Lewis was getting pieced up for nearly three rounds. Yet with just seconds left on the clock — 11 seconds officially — Lewis landed what he later called a “million dollar punch” that helped him snatch victory from the jaws of defeat. Yet before the big shot landed, Lewis said he suspected there might be MSG stakes packed into his fist.

“I kind of felt like they would [ask me to fight Cormier] because I was No. 2, with Stipe [Miocic] coming off a loss,” he says. “But that fight right there, I told my coach it would be great if I could have one of them Rocky Balboa type fights because I’m fighting a guy from Russia, and I’m from America. It was just like a Rocky fight.”

Now he’s fighting a fellow native Louisianan in Cormier, who eight years ago — right around the time he was making his MMA debut against Nick Mitchell in Worldwide Gladiator — crossed paths with him when Strikeforce visited Houston.

“In 2010, Strikeforce came to Houston, and DC was something like 5-0 or 6-0, and I’d seen him at the expo,” Lewis says, referring to Cormier’s fight with Jason Riley. “I seen him walking around and I seen he had a pink cast on his hand, and I was like, this guy is way too fat...because he looked shorter and fatter. Because back then I was slim, I was like 235. So, I was like, man, I could take this guy.”

He has his chance on Saturday night. The fight came together out of necessity, as the UFC didn’t have a viable headliner that would be big enough for MSG. With the dual champion Cormier’s hand having healed, and Lewis’s hot streak of hulk smashing everyone else in the division, it was the best fight available to make.

It helped that the otherwise soft-spoken Lewis established himself as MMA’s greatest cult figure in Las Vegas when he dropped his trunks right there in the middle of the Octagon. After knocking out Volkov, Lewis took off his shorts moments before Joe Rogan could get over to ask him why.

“My balls was hot,” Lewis said.

That sealed it. Lewis had won the crowd over, and picked up over half-a-million Instagram followers overnight. It was the most played sound bite since his knockout of Travis Browne, when he told poor Brian Stann, the game’s most honest professional, “where Ronda Rousey’s fine ass at?”

“I didn’t think nothing of it,” Lewis says. “I took my shorts off to throw it into the crowd, because I was wearing Reeboks underneath I didn’t think they’d make it a big deal. It was just some tights. It was off the top of my head. I didn’t know what to say, but it was off the top of my head.

“That’s just the way I am. My wife knows. That’s why she didn’t get too mad at me over the Ronda Rousey thing, but she knows I joke around a lot and stuff like that.”

The fact that Lewis has ascended to a place in pop culture where people know his character — particularly his sense of humor — says it all. He’s always had that sense of humor, even going back to when he served his time in prison. And while he’s on the outside now, thriving in an altogether different kind of cage — the prize ring, which has earned him not only money but measures of glory — he still remembers the now closed down Central Unit in Sugar Land, Texas.

The UFC’s Countdown crew even visited the old prison yard with him, as a reminder of just how far he’s come.

“It brought back the weirdness,” Lewis says. “Just seeing that the buildings, seeing that even though they looked old, they looked just the same. Everything else was just torn down around it.”

Lewis is fighting for the heavyweight title at Madison Square Garden on Saturday night, while many of the inmates that he knew back there are still serving time. “There’s still a lot of guys serving who were there, and a lot of kids too who were doing life and are still doing time in other units,” he says. But Lewis is free, and he is making the most of his time in the UFC. At one point he contemplated retirement. That time, his wife didn’t like the idea, and so he kept going.

Now he’s on the verge of becoming champion. They say he has a puncher’s chance, yet we’ve seen what Lewis can do with chances. He converts them into new realities. He makes them become endorsement deals and paychecks, turns them into new destinies that not even he could have fathomed.

Not that he ever needed to.

“I’m not in it to be the best fighter in the world, I don’t care about that,” he says. “I really don’t. I tell people all the time that it would be good if they forget about me next week, that they don’t even mention my name anymore.”

As unlikely as his rise has been, at this point being forgotten is even more unlikely. Derrick Lewis has made something of himself, and everyone has seen it.