LAS VEGAS -- Conor McGregor was soundly beaten by Dustin Poirier less than six months ago. That doesn't seem like enough time for the Irish superstar to patch all the holes Poirier punched in his game.
When they complete their rivalry trilogy tonight in the main event of UFC 264, Poirier (27-6) enters the cage as a better-rounded, more tested fighter than McGregor (22-5), who is competing in mixed martial arts for only the fourth time in nearly five years.
Yet McGregor's famed punching power -- and the world's memory of his meteoric rise through his sport -- remain tantalizing enough to create uncertainty in the minds of millions of fight fans. McGregor has done the improbable before, and he'll probably never lose the ability to stoke his fans' imaginations.
"This is my bread and butter," McGregor said. "This is what wakes me up in the morning with fire in my belly. I love to come in here, defy the odds, do the unthinkable and put on a show."
That sounds somewhat like the old McGregor, the former plumber who conquered the MMA world with two heavy hands and an unmatched gift of gab.
But will the same man get out of his luxury car at T-Mobile Arena? Can a self-described "fat-cat" multimillionaire return to his feral, ferocious form for another electrifying victory?
Poirier knows the possibility exists in the conclusion of this three-fight epic that began with McGregor's first-round knockout of Poirier in 2014, then continued with Poirier's second-round stoppage of McGregor in Abu Dhabi.
"I have a healthy fear going into every fight," Poirier said. "I know the dangers. I know what this guy can do."
The winner of the main event gets the next lightweight title shot against champion Charles Oliveira, according to UFC President Dana White.
UFC 264 is co-headlined by a bout between former welterweight title challengers Gilbert Burns and Stephen Thompson. The pay-per-view card also includes a heavyweight matchup between Tai Tuivasa and former NFL player Greg Hardy.
Anyone who saw UFC 257 in January knows how comfortably Poirier handled McGregor's strengths. In the rematch, McGregor must either do his thing much better, or he must adapt and evolve -- something he hasn't done successfully over the past five years.
Poirier highlighted weaknesses and exploited opportunities in the approach that made McGregor the biggest name in combat sports. Patiently implementing his game plan, Poirier battered McGregor with painful leg kicks before finishing him with fists, stopping the former two-division UFC champion on punches for the first time in McGregor's career.
McGregor had a solid first round on his feet, but he did it while using a more conventional boxing stance, not the karate-influenced approach that made him so unpredictable earlier in his career. McGregor showed an inability or unwillingness to check Poirier's leg kicks in that stance until later in the fight, which meant McGregor's right leg was beaten into painful uselessness.
McGregor's coaches have said he will adjust to the kicks, and he might even dish out more of his own, as he did against Nate Diaz a half-decade ago. Improving his aggression could lead to more counterpunching opportunities for McGregor, who thrives on them.
McGregor is no stranger to crossroads moments, but this two-bout series with Poirier could define what's left in the career of a fighter who turns 33 on Wednesday.
Even after McGregor baited and berated Poirier throughout their final news conference Thursday, Poirier is confident he made the right decision to finish the task of erasing another swath of McGregor's mystique.
"It's just business," Poirier said. "I see a man here. It's a fight, and I beat him [last time]. What's his excuse going to be on Saturday?"
