LOS ANGELES -- Conor McGregor underwent three hours of surgery on Sunday, less than 24 hours after suffering a "clean" break of his left shinbone during a devastating UFC defeat to American brawler Dustin Poirier.
Doctors revealed that McGregor broke his left tibia and fibula bones in the opening round of the non-title lightweight bout in Las Vegas.
McGregor said in a video message posted on social media that he expects to be on crutches for six weeks before eventually making a return.
"Conor is in recovery after 3 hours of surgery," McGregor's agent Audie Attar said. "The surgery was successful repairing fractures of his tibia and fibula."
He added doctors were "confident that with time he will make a full recovery. We anticipate his return to the octagon."
Poirier overpowered McGregor on Saturday at T-Mobile arena, winning their trilogy fight by a TKO after the Irishman snapped his left leg in the waning seconds of the opening round.
The fight was officially ruled as a "doctor's stoppage" at the end of the first round after a bloodied McGregor swung and missed a punch then stumbled backwards, his lower leg grotesquely buckling under him near the edge of the octagon.
Poirier then pounced on McGregor, raining down a series of punches and elbows as the bell sounded to end the round. It was the second time Poirier had beaten McGregor in six months.
The scheduled five-round rubber match was expected to settle the score and complete the trilogy between the former two-weight UFC champ McGregor and his longtime rival Poirier, who now looks set to get a shot at an undisputed title and establish himself as one of the sport's superstars.
There was plenty of bad blood between the two in the lead up to their third fight.
McGregor insulted Poirier's wife on social media before the fight and then a second time in the ring as he sat, waiting for the medic to stabilize the leg.
Before the fight McGregor told Poirier he was going to leave the ring in a box. Instead McGregor had to be carted out on a stretcher.
Poirier said his payback was karma.
"This guy is a dirt bag," Poirier said in the ring immediately after the fight. "Karma's not a bitch. She's a mirror."
Promoter Dana White said on Sunday that he hopes there is a fourth Poirier-McGregor fight.
Poirier had his own take on how that might play out. "We are going to fight again whether it's in the octagon or the sidewalk," he said.
© Agence France-Presse