Conor McGregor never backs away from a challenge but this one seems too big.
The Irishman, who has never boxed professionally, believes he can beat the greatest pound-for-pound boxer of the past 25 years in Floyd Mayweather.
McGregor's achievements in MMA are well documented and his 21-3record is highlighted by being the UFC's first simultaneous two-division champion. He remains the reigning lightweight (155 pounds) titleholder.
He knocks out people for fun with that dangerous left hand and his power is unquestioned but this seems an impossible task.
Mayweather, for all his character flaws, is one of the greatest sportsmen of our time and has fashioned a 49-0 record, punctuated by title reigns in five weight classes. This should be an easy fight for him but there's a case to be made for McGregor, although it isn't strong.
The 28-year-old is 12 years the junior of Mayweather and will enjoy a height and reach advantage.
This is a rare code switch that doesn't draw many parallels in the world of sport. McGregor will have to go against many of the instincts he has learned in the past decade.
He won't be able to kick, wrestle or grapple if he gets in trouble and while there's no reason to doubt his approach, the brain reacts in different ways under pressure. He is also moving to Mayweather's world, where Money is the man.
They will wear 10-ounce gloves - McGregor's used to 4-ounce ones in MMA - and that will detract from his punching power.
The bout is being contested at 154 pounds (69.8kg). That weight class requires 10-ounce gloves, or heavier, whereas 147 pound bouts and below can use 8-ounce gloves. Lighter gloves give the advantage to a heavy puncher.
While MMA stats don't compute to boxing, McGregor lands 5.82 significant strikes per minute - eighth best among all UFC fighters with a minimum of five bouts. He's scored 12 knockdowns in 10 UFC contests and seven of his nine UFC wins have come via knockout.
McGregor won't fear Mayweather's fists as the American has won only one of his past 10 fights via stoppage. McGregor, a southpaw, has unique movement that will be nothing like Mayweather has encountered.
But Mayweather is a defensive genius; Manny Pacquiao (59-6-2) landed only 19 per cent of his punches against Money in their 2015 mega-fight. He's supremely fit and has no problem being in perpetual motion for 36 minutes.
In many of McGregor's recent bouts, he has met an opponent happy to stand in front of him with limited head movement.
McGregor likes to push the pace with aggression but his cardio has been iffy. If he doesn't get tired chasing Mayweather around the ring, he might get frustrated if he can't land a shot.
The wildcard is whether Mayweather's two-year hiatus will hinder him. He last fought against Andre Berto (31-5) in September 2015 in his "retirement" fight.
Floyd Mayweather Jr. Photo / AP
What is unique about this clash is the way it has drawn so much interest. Social media has been buzzing and even if diehard fans complain that it could be damaging to their respective disciplines, they will still likely tune in.
Boxing fans have been dealt a raw deal for so long that this is one of the rare occasions where promoters have responded to buyer demand.
Granted, the money on offer is what has made this work, as the total revenue could top US$500 million, but you can't knock those involved for putting it together. The trash talk leading up to the fight will be worth watching, too.
This is a once-in-a-lifetime bout. McGregor is one of the few MMA fighters to garner significant mainstream interest, while Mayweather has made hundreds of millions as a pay-per-view giant.
A McGregor win will boost the profile of MMA, while if he loses, which seems highly likely, some will (incorrectly) continue to view mixed martial arts as a sideshow.
Mayweather can also move to 50-0 and surpass former heavyweight champion Rocky Marciano's magic mark of 49-0.
Regardless of the result, McGregor has already won in many respects. He's talked his way into a fight in Las Vegas that will net him as much as US$100 million - money MMA fighters have spent the past 20 years dreaming of.
The brash brawler is potentially one more left hand away from producing one of the biggest upsets in sporting history.
THE FIGHT
When: Sunday,August 27 (NZT) Where: T-Mobile Arena, LasVegas The rules: The fight will be held under boxing rules, with the fighters using 10-ounce boxing gloves instead of the smaller UFC gloves. McGregor will not be allowed to use the leg kicks or take downs used in MMA. Odds: 11-1Mayweather
