Nurmagomedov and Diaz had to be separated from one another at UFC 239 in Las Vegas following a heated exchange of words.
Fan footage from the sixth pay-per-view card of the year showed Diaz exchanging words with the reigning lightweight champion as he took to his seat, which was in the row behind the Russian.
As he edged towards his seat, Diaz was goaded by Nurmagomedov’s team-mate Islam Makhachev, prompting the Ultimate Fighter season five winner to walk towards the pair with his hands up.
Security swooped in before the trio moved within touching distance and Diaz was promptly escorted from the vicinity.
Diaz’s actions didn’t sit well Nurmagomedov’s dad – Abdulmanap – who believes the 34-year-old instigated the incident to try to insert himself into the lightweight title picture.
“This guy is trying to get what he deserves without standing in line,” Abdulmanap wrote on Instagram.
“How many [times] we asked him and [Anthony] Pettis for the fight? it was difficult to reach agreement with them. But the UFC can give that chance to this guy.”
UFC president Dana White was quizzed about the near-melee in the post-fight press conference and revealed it was the result of the pair ‘talking s**t to each other’.
“They got into a fight, Khabib and Diaz, talking s**t to each other back and forth,” said White.
“Everybody broke it up, we moved Diaz and then Diaz left after the [Gilbert] Melendez fight.”
He later added: “Everybody got it [contained] before it became anything other than verbal.”
The altercation between Nurmagomedov and Diaz isn’t the first time they’ve nearly come to blows.
The pair clashed at World Series of Fighting 22 in Las Vegas, with Diaz aiming a number of punches and slaps Nurmagomedov’s way before his brother Nick threw a drink over the Dagestan native.
Diaz reflected on the infamous brawl during a recent appearance on Ariel Helwani’s MMA Show, in which he ruled out returning to lightweight to fight ‘The Eagle’ because he already owns a ‘victory over him’.
He said: “Khabib? I already slapped him in his face, I already told you guys that. And I beat Conor before him, quicker than him, easier than him.
“He’s a little big-headed right now. I don’t need to fight him anyway because I already got a victory over him.
“So he’s just gonna hide out and play champ and act like a good guy and f*****g Mr. F*****g Humble F*****g Khabib.
“I’m not buying that s**t.”
Diaz make his long-awaited return to the Octagon next month at UFC 241 in Anaheim, California, taking on former lightweight champion Anthony Pettis.
Nurmagomedov, meanwhile, will defend his lightweight crown against interim 155lbs champion Dustin Poirier this September at UFC 242, which takes place in Abu Dhabi.