Nearly eight years ago, Anthony Johnson made the most auspicious of UFC debuts, needing just 13 seconds to defeat Chad Reiner.

It was impressive, to be sure, but Johnson wasn't really viewed as a title contender in those days. Tough? Absolutely. Physically gifted? For sure. But legitimate contender? Nah.

He was a curiosity more than anything else, just like 300-pound Jared Lorenzen was a curiosity more than a prospect as an NFL quarterback. Or, similarly, the way 7-foot-7 Manute Bol was a curiosity more than a Bill Russell-esque defensive force in the NBA.

Johnson was this freak of nature who could drop 40 or 50 pounds seemingly at will to make the UFC's 170-pound welterweight limit.

View photos The winner of Alexander Gustafsson, left, vs. Anthony Johnson will face champion Jon Jones. (Getty Images) More

And even after it became apparent that he was only fooling himself by trying to make 170, he remained a curiosity. He was incredibly athletic for a big guy; he could do things that few people have the ability to do.

Big, most assuredly. But the next big thing? Well, let's just say that mentions of Johnson's name alongside the words "UFC champion" were few and far between.

In 2014, though, something changed dramatically.

It no longer was unreasonable to consider Johnson, 30, a title contender. Even though he brushed aside title talk at the post-fight news conference after an eye-opening, one-sided victory over Phil Davis at UFC 172 in April, it was obvious to all who watched that this was a different man than we'd seen before.

There was a seriousness to his demeanor and an intensity. He no longer had all the answers. He wasn't looking to go out for a night on the town after practice.

And now, days away from the most significant fight of his life, a match in Stockholm in the main event of a UFC card to be broadcast nationally on Fox, this is the most amazing thing:

Anthony Johnson is an honest-to-goodness legitimate contender for the UFC's light heavyweight title.

Johnson meets Alexander Gustafsson on Saturday at Tele2 Arena. With 25,000 tickets already sold, a crowd of around 30,000 is expected to cheer on Gustafsson, the local hero and the man many believe is the UFC's uncrowned light heavyweight champion.

The winner of the fight will meet Jon Jones for the light heavyweight championship, probably in the summer in Las Vegas.

And while Gustafsson is about a 2 ½-to-1 favorite to win, according to the online sports book Bovada, which would set up a heated rematch with Jones, he knows full well what he's up against.

"He has incredible power and is very good at knocking people out," Gustafsson said. "It wouldn't be very smart to be thinking of Jon Jones or anyone else when I'm facing someone like that, who can hit like Anthony Johnson."

Johnson now has the look of a serious athlete who knows he's capable of big things. It's a marked contrast to the Johnson who was anything but serious during his first stint in the UFC.

After getting cut, after failing repeatedly to make weight, after looking like anything but a professional, Johnson has clearly changed his ways.

Making that change started at the top.

"I've switched my life around," said Johnson, who is 2-0 since returning to the UFC in 2014, "and that's gotten me to where I am today. Basically, I stopped listening to myself and started listening to what my coaches had to say."

Think about that for a second: I stopped listening to myself.

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