In the early hours of Sunday morning (GMT) Conor McGregor will take on Floyd Mayweather in one of the strangest boxing matches to ever be sanctioned. The greatest boxer of his generation will fight the most famous mixed martial artist with the reputations of both men, and their respective sports, potentially on the line. The sheer existence of this event is a victory for McGregor. Regardless of the outcome, the Irishman will make an astronomical sum of money and confirm himself as a once-in-a-generation phenomenon who willed the richest fight of all time into being.

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UFC fighter and Sky Sports analyst Dan Hardy offered this summary to Square Mile.

“First and foremost, the fight itself puts mixed martial arts in a level position with boxing and we have been waiting for that for a long time. Even if Conor McGregor lands a glove on Floyd Mayweather, then it’s a victory for mixed martial arts. For anyone that watched the world tour, McGregor already has a victory and it’s the first time I’ve seen Mayweather a little shaken ahead of a fight.

“Mayweather has beaten every man he has faced in the professional boxing ring. Every one of those 49 men were boxers. If 49 have tried and 49 have failed, surely it’s clear that all traditional boxing approaches are useless against the masterful work of Mayweather. It’s McGregor’s opportunity to show him something different He is a fighter, a combat athlete of the highest level. There’s always a possibility when you have the punching power like McGregor has.

“They are both such polarising characters in their own sport and you get the best performances under that type of pressure.

“Looking at it from a mixed martial arts perspective, McGregor isn’t risking a lot with this fight. At the end of the day, whatever happens, he is still the better fighter. He is making more money in this fight than he ever has in his career, so it’s a massive opportunity for McGregor. As long as he puts on a good show, then it bodes well for him whatever he decides to do in the future.”

But what happens if McGregor actually wins? How would his victory affect combat sports? Let's take a look at the potential consequences for those involved...

The immediate consequence for Mayweather would be ridicule. He would be the boxer who claimed to be “the best ever” and then lost to an opponent having their first professional boxing match. While many great boxers have endured one fight too many, they all did so against other boxers – not novices to the sport.

As Adam Guillen of MMA Mania notes: “It would obviously tarnish Floyd's mint record, and it would add insult to injury, as well, as the loss will have come against an MMA fighter with no boxing experience as opposed to a legit boxing veteran.

Wil Esco of Bad Left Hook is more uncompromising. “I mean, look, if Conor McGregor were to beat Floyd Mayweather it would be an unthinkable embarrassment. Not only does it ruin the branding and credibility of the self-proclaimed 'TBE', but it also undermines the discipline of boxing as a whole - having a complete novice walk in and beat one of the best fighters in the sport's long and storied history.”

In defeat, there are only two options for Mayweather: retirement or a McGregor rematch

Indeed the opprobrium would be magnified by the fact a Mayweather defeat would be perceived as a defeat for boxing: fairly or not, Floyd becomes the man who betrayed an entire sport, and that sport’s vaunted history. Many will never forgive him for this.

Yet it isn’t all bad news. In defeat, there are only two options for Mayweather: retirement or a McGregor rematch. He almost certainly chooses the latter, and makes even more money the second time around.

While Mayweather would always face ridicule for his loss, Floyd defenders could legitimately cite his age as a mitigating factor: the Old Man normally loses to the Young Man. He would still be a lock for the Hall of Fame. And while his boxing record is forever tarnished, his legacy as a pioneer of combat sports is probably burnished by defeat – and its aftermath.

For McGregor, the equation is even simpler: beat Mayweather and become the most famous athlete on the planet. As Guillen states: “If Conor can somehow defeat ‘Money’ it would be monumental. He will have lifetime bragging rights, and will have the right to say he conquered both boxing and MMA.” His ego acquires its own gravitational pull; his net worth makes Midas blush; and everyone in combat sports wants a piece of him.

Over to Esco. “With a win he'll have a licence to print his own money. McGregor would become a legitimate draw in both sports and have his pick of the litter when choosing who, and in what forum, he wants to compete from here on out.”

The who and what forum would most likely be Mayweather in a boxing rematch. McGregor’s showmanship and love of mammon makes retirement unlikely, and that fight would offer the best platform for both. There might be some talk of Floyd stepping into the Octagon, but if he loses to McGregor on ‘home turf’, what’s the point of a rematch under rules that hugely favour the Irishman? No, back to the ring we go.

A win makes Conor McGregor the biggest star combat sports has ever seen

After Mayweather II? Most likely Mayweather III, provided Floyd wins the rematch. Having lost three times in his career, McGregor has no ‘0’ to fetishize, and defeat would not dent his pulling power, only ramp up the value of the trilogy bout.

Does he ever return to the Octagon? Probably not. Boxing is the more lucrative and (in his eyes) safer option, and the UFC simply wouldn’t be able to afford him. Why fight for a promoter when you can make more money fighting for yourself? Why fight for millions when you can fight for hundreds of millions?

Does he ever fight anybody not named Floyd Mayweather? Unlikely. No other opponent could generate anything close to the numbers Mayweather guarantees. A third MMA fight with Nate Diaz, or a boxing match with, say, Canelo Alvarez, both earn McGregor another fortune – but not Floyd money. Only Floyd brings Floyd money. Well, only Floyd and the man who defeated him.

Whatever happens, Conor would be calling the shots. Esco puts it concisely: “A win makes Conor McGregor the biggest star combat sports has ever seen.”

A Mayweather defeat is disastrous for boxing’s credibility. The perception of the sport in the eyes of the public is immeasurably damaged, possibly irreparably. It becomes a 20th century discipline in the age of the 21st.

Martin Theobald of New Age Boxing doesn't mince words. “The fallout from a McGregor victory is incomprehensible. Mayweather, for all his personality deficiencies, has carried the sport of boxing in the spotlight for 15 years. If his final act is to pass his legacy to a man from another sport, boxing will suffer as a whole. Never can a boxer claim to be an elite fighter if their own flagship is sunk by an outsider.”

The most obvious way to regain boxing’s lost honour would be for a boxer to step into the Octagon and defeat a leading mixed martial artist. But which boxer would be willing to take such a risk – with comparatively little financial reward? Other than Ronda Rousey, McGregor is the only MMA fighter to attain mainstream recognition, and the earning power that comes with it. Anthony Joshua earns infinitely more money fighting his American rival Deontay Wilder than his UFC equivalent Stipe Miocic.

Every boxing fan would be forced to endure constant reminders that Mayweather lost to McGregor

Other than nobodies with nothing to lose (and frankly who then cares?), the only boxers tempted to crossover would be ageing former champions / contenders, losing relevance but still more famous than their UFC counterpart. (Amir Khan is a good example.) Perhaps one of these crusaders scores a flash knockdown and can claim to have avenged his sport. Perhaps some people might even believe him.

In short, boxing would mostly continue as before: a few good fights, a lot of lousy fights, and the odd global showpiece. But every fighter, and every fan, would be forced to endure constant reminders that Mayweather lost to McGregor. And nothing could ever change that.

Here’s where matters get really interesting. Short term, it would give MMA a massive boost in both credibility and visibility: it would be the sport which spawned the destroyer of the unbeaten Mayweather. Its technical, and moral, superiority over boxing would be hard to argue.

UFC, as the principal platform of MMA, would also benefit. "Dana White will undoubtedly be gloating,” says Guillen, “albeit in a more reserved manner than Conor.” No doubt: McGregor is still contracted to the MMA, and his victory would burnish the credentials of every fighter on the roster. (As well as distracting from Jon Jones’ recently failed drug test.)

However, as already noted, a McGregor victory massively diminishes the likelihood of a McGregor return to the Octagon. And the UFC’s problems could soon grow bigger than its star attraction going AWOL. The UFC’s stranglehold on MMA allows the organization near-total control of its fighters: rather than negotiate the highest payday, fighters must take the opponent of the UFC’s choosing. (In fairness, the two are rarely divergent.) This has engendered an environment in which the best take on the best – in stark comparison to boxing – but left fighters beholden to the whims of the UFC matchmakers.

MMA would gain respect – but would it gain commercial appeal?

But what if boxing suddenly became a legitimate option? A sport with less danger (theoretically), more earning opportunities, greater visibility, and the chance to control your own fate. UFC middleweight champion Michael Bisping recently called out Tony Bellew, while Jimi Manuwa has previously challenged David Haye – both under boxing rules. Rather than force boxers into the Octagon, a McGregor victory would more likely open the door for MMA fighters to try their hands in the ring.

MMA would gain respect – but would it gain even greater commercial appeal? Undoubtedly interest would spike, and the victory would be a landmark moment for the sport. A personal view is the ground fighting, the wrestling on the mat, will always put off the casual viewer. The moves are too complicated, and too visually sedate; it’s no coincidence that McGregor prefers to fight standing up. (He started out as a boxer.) But then considering the remarkable growth of the UFC, only a fool would argue this with any certainty.

Hardy says it best: “Whichever way the fight goes, on Sunday morning there will be a lot of talking points, and it’s a fight we will be talking about for years to come.”

We might as well enjoy it while we can.

Follow Dan Hardy on Twitter @danhardymma

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