With 10 seconds left in the first round against Poirier at UFC 264, McGregor's leg appeared to bend in half right by the ankle causing him to let out an ear piercing scream and go down on the mat. Poirier would land a few more blows while McGregor was down before the bell sounded. McGregor could not stand on his own after the incident and was carted out of the ring on a stretcher.

One of the more ironic aspects of the fight was all the over-the-top trash talk from McGregor before the fight including things like "I'm going to murder him" and "he'll be leaving on a stretcher", when in fact it was McGregor who ended up leaving on the stretcher. Despite the animosity and just plain disrespect from McGregor, Poirier showed he was the bigger man not engaging McGregor in such talk, and even wished him a safe return home to his beautiful family in a post-fight interview.