UFC president Dana White said that three men had been arrested following the fracas.
McGregor was making his comeback to mixed martial arts after a near two-year hiatus but the former two-weight champion submitted to his rival’s rear-naked choke midway through the fourth round in Las Vegas.
Nurmagomedov therefore retained his lightweight title but then threw his gumshield, mounted the cage and looked to attack someone from McGregor’s team.
A prone McGregor, still sitting on the floor after his defeat, was attacked by someone from Nurmagomedov’s camp as the bad blood that has been building up ahead of this fight came to a head.
Welterweight champion Tyrone Woodley, working on BT Sport, explained: It went into complete pandemonium. Khabib jumped out the octagon. He went after Conor’s team-mate Dillon.
“Then Khabib’s coaches went after Conor after he was recovering from a loss. It was complete chaos.”
“This is absolutely the craziest moment I have seen in all my years calling fights,” declared UFC commentator Joe Rogan.
Twitter users described the scenes as “madness” with one user commenting, “All hell breaks loose at UFC229.”