The pair of lightweights were both in attendance and cageside at the T-Mobile Arena, where champions Israel Adesanya and Alexander Volkanovski both retained their titles.
Former welterweight champion Gilbert Burns filmed the altercation, lasting just over 30 seconds, where Poirier and Chandler looked incredibly angry.
Security stepped in to stop things getting physical in Las Vegas, while Jiri Prochazka, current light heavyweight champion, restrained Poirier.
Poirier, in a colourful shirt, appeared to call Chandler “a fake motherf****r, also adding, "I’ll f*** you up". Chandler's response could not be heard in the clip but one can assume it wasn't pleasant.
The two have gone back and forth in the past, including a verbal joust on the MMA Hour with Ariel Helwani.
In a separate appearance, Poirier said he was unimpressed by Chandler's victories over Dan Hooker and Tony Ferguson and claimed "he’s never beaten anybody coming off of a win in the UFC.
He also expressed his interest in fighting Chandler in the future.
Both men have had lightweight title shots and succumbed to the same result against former champion Charles Oliveira.
There appears to be a genuine disdain between them and it only feels right that they settle their scores inside the Octagon.
But this week, Chandler challenged Conor McGregor, who is still on the mend following his leg break suffered against Poirier in July 2021, for his comeback fight.
And he wants the bout to take place at welterweight.
"I do believe that Conor McGregor has to come back and fight somebody so why shouldn't it be the other most electrifying, most exciting guy - not just in the lightweight division but on the UFC roster," he told SPORTbible.
"I want to do it at 170lbs. I want him at his biggest, his baddest, his best and his most dangerous. So come and get you some, holla at me - this winter or the first of next year."
Featured Image Credit: Image: Gilbert Burns
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