Former UFC heavyweight Brendan Schaub has sent a blistering warning to MMA legend Nate Diaz after the Stockton native took a very personal shot at Schaub over social media.

Last week, Schaub revealed on his podcast that his good friend, former Interim UFC Heavyweight Champion Shane Carwin, was struggling with the impact of brain damage from his fighting career.

Schaub, who trained with Carwin for many years, was in tears over his ex-teammate’s predicament.

Hours later, and out of the blue, Diaz took a personal shot at Schaub on social media, writing: ‘Brendan the big ol p***y Schaub’ alongside a crying emoji.

This week, Schaub addressed Diaz’s response to his emotional update.

‘I retired 15 years ago, man,’ Schaub said.

‘That being said, that’s social media. This isn’t real, because here’s what’s real: I will f**k you up. That’s real. I’m not asking for this. I don’t want to f**k him up, I’m not trying to f**k him up. 

‘End of the day, if he walked in here right now, only one of us is going to walk out unscathed, and it’s me. Every f**king day of the week, 365 days a year, I will snap his f**king neck.’

Schaub went on to explain that he respects Diaz’s fighting career, but he is simply a much bigger man.

‘I’m 245 pounds, trained black belt, top-10 UFC heavyweight in the world at one point, I’m not out of shape. I’m a beast when it comes down to it,’ Schaub explained.

‘I know, I tell jokes, I do crazy s**t, I made some mistakes… I get all that. At the end of the day, the way this works, I’m not a civilian like the rest of his goons around him. I’m not this fake gangster, I don’t go looking for fights. I know I’m tough.

‘I don’t have to get on Twitter and blast it out, and prove it every day because I’m insecure, because of whatever shit he has going on with his childhood trauma. I don’t have to do that. At the end of the day, I will twist your f**king neck off.

Schaub, who retired from the Octagon in 2014, says he’s not looking for a fight with Diaz – but he won’t back down from one. 

‘What are you going to do Nate? What are you going to do? You going to volume punch me?’ Schaub said. 

‘That’s what you’re going to do? What are you going to do, out grapple me?

‘Now, if you’re doing this because you fancy yourself [some] fisticuffs, if you fancy yourself [and] you want to actually grapple me, I’m not hard to get a hold of.’

Diaz has since responded to Schaub’s blistering tirade, simply posting to X: ‘I think you’d be surprised.’

The cryptic remark is a reference to an infamous public conversation between Joe Rogan and Schaub in 2014 in which the UFC commentator delivered some hard truths about the heavyweight’s future in the sport.

Rogan asked Schaub how he would fare in a wrestling match against then UFC heavyweight champ Cain Velasquez, to which Schaub replied, ‘I think you’d be surprised.’