The Irishman suffered a brutal, freak suspected broken left ankle with just seconds left in a wild first round at T-Mobile Arena in Las Vegas.
McGregor appeared to roll back heavily on the ankle and trapped it under himself after both men had missed with attempted strikes from close range, with the severe damage becoming apparent after the horn had sounded with ‘Notorious’ sitting with his back against the octagon and the bout quickly waved off as he received medical attention.
The enforced stoppage means Poirier has now won back-to-back fights against McGregor, leading their heated rivalry 2-1 following his shock stoppage win at UFC 257 in Abu Dhabi in January.
“I felt something, for sure,” Poirier said afterwards as tempers flared, even with McGregor receiving treatment.
“He fractured it on one of the kicks at the beginning of the fight, and then he broke it.”
As his leg was put into a splint and before he was transported away, McGregor bellowed: “This is not over.”