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On Wednesday, the impossible dream, the flight of fancy, the ridiculous notion became reality: Floyd Mayweather, owner of all sporting pay-per-view records of note, will exit a two-year retirement for the August 26 boxing match against Conor McGregor, the brightest star mixed martial arts has ever seen.

McGregor is the highest-paid Ultimate Fighting Championship athlete ever, but the leap he is about to make is an extraordinary one. He says he'll go from his comparatively low estimated paydays to over $100 million in one night.

And then, according to UFC President Dana White, he'll come back to the UFC for a lightweight title defense in December, where he will presumably go back to making $3 million guaranteed for his fights. From $100 million to $3 million, for the same amount of work.

Sure he will.

For as much as White spent Wednesday's conference call promoting him as a fighter's fighter, someone who will step up and fight anyone at any time, reality is shaded differently.

I think White has the same gut feeling I have, which is: that win over Eddie Alvarez last year? That was probably the last time we'll see McGregor in the Octagon.

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When I traveled to Dublin back in 2015 for a Bleacher Report profile of McGregor, I was largely struck by two things I did not know about the man.

The first was his unwavering belief in The Secret, the millions-sold New Age self-help book that tells of the power to will things into existence by visualization.

Sitting in the backyard of their parents' charming Crumlin home, McGregor's sister told me about the time Conor discovered her DVD copy of the film version of The Secret (after previously ignoring her advice that he read the book) and how that discovery had been the thing that changed her brother's life forever. Everything had been different since that moment, his parents agreed.

McGregor told me in 2015 how he and his girlfriend, Dee, began practicing what the film taught:

"They started concentrating on the things they wanted. At first, they focused on small things. They would drive to the local shopping center and focus on securing the parking spot closest to the door.

"'We would be driving to the shop and visualizing the exact car park space,' he says. 'And then we'd be able to get it every time.'

"They kept visualizing small things, seeing the law of attraction play out in front of their eyes. Eventually, the small things turned to big things: dreams of wealth, success and fighting championships."

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I'll admit, my internal skeptic found the whole thing a bit laughable.

But then McGregor knocked out Chad Mendes and Jose Aldo and, well, let's just say the copy of The Secret I purchased while researching that 2015 story is now more than a little dog-eared. Though I've yet to successfully visualize into reality a great parking space, much less two UFC championships.

The second thing I learned was more subtle but far more surprising: McGregor did not plan a long, historic career in mixed martial arts.

The McGregor plan, from the very beginning, could be distilled into six simple words: Get in. Get rich. Get out. The whole point of creating this meteoric rise to the top was not so he could stay there for an extended period of time, fighting off new challengers to his throne and participating in classic fights for the thrill of the fans watching in the arena and at home.

The reason McGregor had to reach the top so quickly, why he visualized and pushed for the kind of dramatic leaps that led him to this point, was because he didn't plan on sticking around. Even two years ago, before the whole Mayweather thing was even an idea in his head, the people closest to McGregor were telling me he had no intention of being in this for the long haul. He wanted to make enough money for generations of his family to never have a financial worry. He wanted to create multiple streams of income that could continue to bring in millions after his career came to a close.

Despite a prodigious spending habit, he has already accomplished these goals.

But it is the potential influx of $100 million for a single night's work that creates the most difficult scenario for UFC owners WME-IMG. After that kind of payday, how can McGregor possibly be enticed to step back into the Octagon for a meager salary of less than $10 million?

Peter Carroll and Sean Sheehan, Irish mixed martial arts journalists who have covered McGregor for the Irish Mirror and leading Irish MMA website SevereMMA since long before he became a household name, both said it is tough to imagine the UFC enticing McGregor back into the fold.

"McGregor's will to compete and prove himself is second to none. But he wants each of his fights to outdo the last in terms of spectacle and purse. He's going into what Dana White believes will be the biggest pay-per-view of all time, which is guaranteed to be the biggest payday of McGregor's life," Carroll said. "Can the UFC put something together that is interesting and lucrative enough for McGregor after he secures such a gargantuan payday against Mayweather?"

"Practically his whole career has been on an upward curve, both in terms of financial reward and pay-per-view numbers. The fight with Mayweather is going to blow all of that out of the water again. Presently, it doesn't look like there are any fights in MMA which could come close to that," Sheehan said. "Whether it's a lightweight title fight, Nate Diaz, Georges St-Pierre or Tyron Woodley, the pay-per-view numbers and paycheck are going to be high. But they'll be significantly lower than what he earns against Mayweather.

"It's going to be extremely difficult for McGregor to go back to MMA after his fight with Mayweather," Sheehan continued. "Now, there is always the possibility he comes back because of his competitive nature. But he doesn't need to."

Higher than financial security on McGregor's list are issues of health and long-term wellness.

There is a hyper-awareness of traumatic brain injury-related issues surrounding aging American football stars. Mixed martial arts is too young to have gone through the same issues with retired fighters as boxing has, but logic would seem to dictate that fighters who spend years being punched and kicked in the head will eventually suffer the same sort of fate.

It is not a fate McGregor is interested in.

"I am not stupid. I am a very bright guy. I know that in the fighting game, you get people who get brain damage and do themselves long-term harm," McGregor told GQ UK in 2015. "I am going to get very, very rich and then I will get out and we will see what comes after that."

A UFC championship is the culmination of a lifelong dream for other fighters. But it is merely a means to an end for McGregor. It is another stop on a road with many branching paths.

"He doesn't want to end up like (Muhammad) Ali. He wants to keep his sharpness," a source close to McGregor said in 2015. "Fighting isn't Conor's goal. It's how he reaches his goals. I don't think people understand that about him. There's a lot more to him than he shows."

Perhaps Dana White truly did believe he was telling the truth when he told SportsCenter he "thinks" McGregor is coming back, though his qualification of that statement is probably more telling than even he realizes.

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Of course, there's every chance White is well aware of the McGregor-less future he and his bosses might be facing and is simply giving lip service to the idea the Irishman will be back in the fold by the end of the year.

But throwing your full belief behind that idea would mean tossing aside everything we know of McGregor's history. His ascension to the featherweight title followed quickly by abdicating the throne. Beating Nate Diaz in their rematch, then expressing little interest in a third bout that would decide the ultimate victor. Flatlining Eddie Alvarez for the lightweight title, then moving on to a different sport entirely.

It would mean ignoring his various business interests.

Hell, it would mean ignoring the hints McGregor himself has given on social media.

Fans of mixed martial arts recoil at the notion of a fighter in his prime, at just 29 years old, hanging up the gloves for good. That sort of thing just isn't done.

But when has McGregor ever done things the way others do them? When has he ever stuck to any kind of script except the one written and visualized in his own head?

He hasn't. McGregor marches to his own beat and charts his own path. Always has and always will.

And fans of mixed martial arts should prepare themselves for the very real possibility that McGregor's win over Alvarez last year was the final time we'll ever see him in the Octagon, no matter what happens in the boxing ring later this summer.