NEW YORK – This is why we love the fight game, isn’t it? Stephen Espinoza, promoted earlier this year to president of sports and event programming for Showtime, took to Twitter on Friday to say, “Congrats, UFC. You’ve far outdone boxing in terms of shadiness.”

On Saturday, UFC president Dana White came to the post-fight news conference following UFC 223 at the Barclays Center in Brooklyn and called Espinoza “a greasy, slimy rat.”

And in Las Vegas on Saturday, superstar boxer Floyd Mayweather said he’s retired from boxing, but would love to fight as a featherweight in White’s UFC. If he would have stopped there, it would have been fine.

He didn’t stop there, though. Of course he didn’t. He added that CBS/Showtime must be involved.

“Retirement has been great but as you know and everyone knows, I go in retirement and I come back,” Mayweather said Saturday during a Showtime boxing broadcast from the Hard Rock in Las Vegas. “It is possible I do come back, but if I do come back, it has to be in the Octagon.

“I spoke with my team, I spoke with [adviser] Al Haymon. Al Haymon says no. I spoke with Showtime, I spoke with CBS. If I do come back, Showtime and CBS has to be involved.”

Apprised of Mayweather’s words, White snarled and said, “Yeah, that ain’t happening.”

And so welcome to the start of what could be the biggest fight promotion in the history of all fight promotions. If Mayweather fights in the UFC – which I say is an extreme long shot – it would shatter all existing pay-per-view records. The conversation would start at 5 million pay-per-view sales in the U.S., and it could be significantly higher.

A large part of the reason that Mayweather was so successful at selling pay-per-views during his 50-0 boxing career was that he knew how to manipulate people. He engendered great loyalty among his fan base, and they supported him with a rare kind of passion.

At the same time, he enraged vast scores of others, and those fans bought his fights in the hope of seeing him lose.

Now, with him debuting in the UFC, trying another sport, the likelihood of someone kicking him in the head or face and knocking him out is that much more likely.

It will sell, sell and sell (a lot) more.

But do we have the stomachs for this? If it happens, it’s going to be filled with nastiness. White and Espinoza worked together promoting the 2017 boxing match between Mayweather and ex-UFC lightweight champion Conor McGregor, and it wasn’t pretty.

If you believe Espinoza, the fight sold 4.4 million on pay-per-view and was the second-highest seller of all-time, behind on Mayweather’s 2015 win over Manny Pacquiao, which did 4.6 million.

White, though, insists the fight sold nearly 7 million and is the all-time sales leader.

The answer to the difference could be as simple as looking at the universe. It is common in boxing for promoters and TV executives to refer to the pay-per-view figures in terms of U.S. sales. White was talking about worldwide sales.

The Mayweather-McGregor promotion left Espinoza and White at odds, and White vowed to never work with Espinoza again. He doubled down on that after a successful UFC 223 that he said set the paid gate record at Barclays Center, home to so many major boxing matches broadcast by Showtime.

It’s almost inconceivable that Mayweather, who is 41 now, will ever step foot into the Octagon. He worked long and hard to get that 50-0 record, and is rightly proud of it. There are billboards around his hometown in Las Vegas that are black with the gold lettering, “50-0.”

This isn’t a guy who is ready to take a one-sided loss just for a payday, no matter how large.

Or, is he?

He’s hired UFC welterweight champion Tyron Woodley to train him, and Woodley said on “UFC Tonight” that he thinks Mayweather has a possibility of success in the UFC.

“Blocking kicks is really easy,” Woodley said. “Once you get to the point where Floyd Mayweather is at, you can see that his boxing, his defense, his ability to see a punch coming in a fraction of a second and avoid or evade that punch, comes from repetition. Drilling over and over and over again. So that’s all we would have to do to utilize blocking kicks. If you look at mixed martial arts as a sport, there are guys that are in the UFC that don’t have a four out of five in their wrestling or jiu-jitsu, so therefore, it’s not kind of crazy that someone with some of the best boxing we’ve ever seen may be able to hold his own.

“Obviously, every round starts on the feet. Every fight starts on the feet, and if you can keep it on the feet, I think that he can hold his own with pretty much anyone in that weight division. My job is to really just help him avoid being taken down, using angles, using footwork, using defense, how to get back up if he gets taken down.”

If Mayweather were 21 instead of 41, I’d be inclined to say that not only could he hold his own in the UFC, he would become one of its elite fighters and would probably win a championship.

At 41, though, it’s a different story. Even for a guy who is as physically talented as Mayweather, and is in the kind of physical shape that Mayweather is in, it’s asking way too much for him to pick up all the non-striking aspects of the game and compete at a high level.

There are, no doubt, already fighters in the UFC that Mayweather would beat. Guys with stand-up and little ground game would be the best choice for him.

But if he were to take on a high-level UFC fighter, it’s impossible to see how Mayweather wouldn’t wind up with his head caved in fairly quickly.

All of the speculation, though, will just fuel the craze: Will he or won’t he? Can he or can’t he?

When talk first surfaced of a boxing match between Mayweather and McGregor in late 2016, it was dismissed out of hand. The fighters themselves kept it alive on social media, where the fan base ate it up. And with each passing week, it became more and more likely until it was made, to the amazement of so many in both sports.

The same thing seems to be occurring now. Mayweather’s talking about it, and White said he was open to it (Until, at least, Mayweather brought up the part about working with Espinoza). No one has believed it, even when Mayweather hired Woodley.

On Saturday, Mayweather told Showtime’s Jim Gray he won’t box again, but didn’t rule out a UFC fight.

“You got to talk to Showtime, CBS,” Mayweather said. “The money is going to be crazy. I can do whatever I want to do. I’m Floyd Mayweather.”

Well, not everything. He didn’t spend the summer of 2012 locked up at the Clark County Detention Center because he liked the food at the commissary, but we get the point.

It says here that he won’t fight in the UFC, despite the talk, and if by some stunner that he does, he’ll get pummeled if he fights anyone but the greenest fighters.

The only thing I am certain of is that it will sell massively well.

Whenever someone puts up an over-under prop on the pay-per-view, take the over. If it happens, this thing will be humongous.

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