McGregor, the brash Irishman who at one point held UFC titles in both the featherweight and lightweight divisions, and Nurmagomedov, the current lightweight champion, took the stage Thursday at Radio City Music Hall in New York City for the first step in promoting what many call the biggest fight in MMA history.
They will meet in the main event of UFC 229 on Oct. 6 at T-Mobile Arena in Las Vegas, but neither held back at their initial news conference together.
"I'm going to truly love putting a beating on this little glass-jaw rat," McGregor said of Nurmagomedov. "He's fought absolutely nobody. He's in over his head. I'm going to pick him apart and absolutely maul him. He's dead man walking."
Nearly every time Nurmagomedov tried to answer a question, McGregor, dressed in a purple suit, jumped in and spoke over him. Nurmagomedov waited for his chance at a reply and said respect was important to him; he wouldn't play into McGregor's trash talk.
"He can talk whatever he wants," Nurmagomedov said. "He's going to talk, I know. [Oct. 6] is most important when they close the cage doors. [Oct. 6], what are you going to do? I'm going to maul you."
Despite what Nurmagomedov said, UFC president Dana White said he believes the war of words mattered.
"You're not human if it doesn't affect you," White said. "Conor came in and did what Conor does. There's never been anybody better at mental warfare. He's the absolute best of all time."
McGregor reclaimed the UFC spotlight in more ways than one Thursday, with White confirming to ESPN after the news conference that McGregor has signed a new eight-fight deal with the promotion.
Terms were not disclosed, but White said the deal could make McGregor the most money in the sport, especially given his pay-per-view appeal. McGregor's fight with Nurmagomedov is the first fight in the deal.
Nurmagomedov (26-0) is widely considered among the most dominant fighters in UFC history. A native of Dagestan, Russia, he thrives on taking opponents to the ground and finishing them on the mat. He dominated Michael Johnson so badly in their 2016 fight that, while punching his opponent, Nurmagomedov urged him to quit early. Most recently, in April, he defeated Al Iaquinta at UFC 223 by unanimous decision.
McGregor (21-3) has not fought in mixed martial arts since his second-round TKO win against Eddie Alvarez in November 2016. He faced Floyd Mayweather in a boxing match in August 2017, when Mayweather won by 10th-round TKO.
Though he does not currently hold any titles, McGregor strutted onto the stage with two belts he previously won in two divisions. He said he brought his own personal belts knowing the UFC wouldn't give them to him.
When asked about ring rust after his time out of the Octagon, McGregor quickly shot it down.
"We are ready for this," McGregor said. "[I see] domination, his head bouncing off the canvas. He has a glass jaw. I will be prepared for five rounds."