It's difficult to pinpoint the precise date, but Conor McGregor became more famous than the UFC somewhere in the past five years.

Most MMA experts would refer to November 2016, when McGregor beat Eddie Alvarez at UFC 205. The Irish superstar rose to prominence as the first fighter in the organization to hold two titles at the same time, and he was heralded as the sport's unrivaled future.

Or there's the media tour leading up to McGregor's boxing fight versus Floyd Mayweather in August 2017. While McGregor lost the fight, he was in top form building up to it, tossing money, delivering sharp one-liners, and whipping the world press into a frenzy every time he got his hands on a microphone.

Others may refer to the animosity-filled, hyper-charged build-up to UFC 229 in October 2018, when McGregor was scheduled to face off against arch-nemesis Khabib Nurmagomedov for the lightweight title he lost due to inactivity. That battle was the most expensive pay-per-view in the sport's history, and the battle at T-Mobile Arena in Nevada was legendary both inside and beyond the cage.

McGregor lost to Nurmagomedov, who has since retired unbeaten, and his star has been fading rather than blazing brightly since then.

He returned to the Octagon for a January 2020 fight against Donald Cerrone, and he annihilated “Cowboy” in 40 vicious, highlight-reel seconds. But the fight seemed like a lamb being taken to the slaughter, a sacrifice to the MMA gods. Then came the pandemic: McGregor "retired" through Twitter, only to return to the ring against Dustin Poirier nearly a year later.

Call it ring rust or bad luck. Call it being defeated by a superior fighter at the time. However you look at it, the McGregor story took a turn for the worst when he was defeated by a more seasoned, polished, and well-rounded Poirier. After so many months of inactivity, while he was out marketing his whiskey, peddling goods, and selling companies, the guy he defeated back in 2014 came out of the trenches and reminded everyone that fighters need to fight to remain sharp.

McGregor is now in an unusual situation, or, as Kamaru Usman put it, "just a dude in the UFC." He seems at ease, even intimate, a far way from the days when he was fleeing unpaid taxes to the Irish government, battling and training in makeshift gyms, promising the world he was going to become the greatest celebrity of them all.

He now has more money than a small country's GDP, with an estimated net worth of US$300 million, after Forbes named him the highest-paid athlete in the world in 2020, with earnings of US$180 million. This implies he earned more than Lionel Messi, Cristiano Ronaldo, and LeBron James combined.

He's now a father, a spouse, and the ruler of a multimillion-dollar business empire. He has conflicting objectives, numerous obligations, and is no longer a one-in-a-million rapscallion vagrant trash-talking his way to the top of the UFC. The issue is, are we going to see the revival of the UFC's defining legend, or will next month mark the beginning of his last hurrah?

While McGregor has had many big bouts, none may be more significant than his trilogy battle versus Poirier, which is scheduled for July 11 at UFC 264 Live Online in Las Vegas. If he loses against Poirier, he will be 1-2 versus "The Diamond," and 1-4 in his past five bouts if you include his boxing battle versus Mayweather.

This is not an icon's record, but it is typical of the destiny of many legends. Going out on top is difficult, and the lengthy fall down the opposite side of the mountain may be just as difficult.

A loss here would likely put an end to any legitimate talk that McGregor could compete for a belt again, with a return to featherweight – where he dominated with seven straight wins on his way to becoming the undisputed champ in 2015 – also likely to be beyond him at 32 years old, given the rough weight cut.

While McGregor's ego may suffer, his bank account will be OK, with mega-money bouts at welterweight versus Nate Diaz and Jorge Masvidal potentially on the horizon. He could earn $100 million boxing Jake or Logan Paul.

But defeating No. 1 rated Poirier will remove any concerns and set up a championship opportunity versus lightweight champ Charles Oliveira.

You have to think that is the best-case scenario for UFC president Dana White – and owners Endeavour, who bought a controlling interest in UFC parent company Zuffa in 2016 when McGregor was pushing the promotion to heights it never imagined it could reach.

White owes McGregor more than he would ever acknowledge, and a resurrected McGregor as UFC champion would earn everyone involved a lot of money. But the world of professional sports is harsh, and unless you're winning, no one wants to watch you.

McGregor has more to lose than gain in his fight against Poirier. Another loss, and we find ourselves looking at a champion we once believed was unbeatable, now more human than ever.