The fight ended after the first round, which heavily went Poirier's way, came to a close. McGregor was left sitting against the Octagon and a replay (some would say too many replays) showed what had happened: McGregor's lower leg snapped as he squared up against Poirier.
The fight was immediately called a TKO for Poirier by doctor's stoppage, and then the real fireworks started. Poirier breathed fire in his post-win interview after several weeks of taking McGregor's verbal abuse, while McGregor was visibly emotional while he was interviewed still sitting on the floor.
UFC president Dana White later confirmed that McGregor had broken his lower tibia.
Some, including former UFC light heavyweight champion Jon Jones, speculated that McGregor may have fought his last UFC fight, either due to the gruesomeness of the injury or for financial reasons.
Some also dredged up a three-month old tweet from McGregor that eerily described a very similar injury. Many, including Poirier, speculated that the real damage to McGregor's leg was done through calf kicks earlier in the round.
There was also the irony of McGregor needing to be taken out of the Octagon on a stretcher after threatening the same to Poirier leading into the bout.
What's next for McGregor? Well, many have wondered if he'll someday step in the ring against Jake Paul, who is attempting to carve out a boxing career by fighting athletes who are not boxers. Paul for his part lowered his offer. Again.
Former UFC lightweight champion Khabib Nurmagomedov described the fight was good defeating evil and expressed hope that Poirier will capture his old belt against Charles Oliveira later this year.
There was some praise and well-wishing for McGregor.
But there was even more scorn for a fighter who has one UFC win in the last five years, especially when McGregor made a crude remark about Poirier's wife toward the end of his interview.
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