Colby Covington has reignited his feud with former team-mate Dustin Poirier, labelling the lightweight star a 'pr***' while claiming the 32-year-old mistreated an amateur fighter in training.

There is no love lost between welterweight contender Covington, 33, and his old team-mates at American Top Team. 

The mouthy American parted ways with the gym last year after failing to abide by their 'no trash talk' rule, having made stinging remarks about the likes of Poirier and Jorge Masvidal.

Covington and Poirier first fell out in 2019 when Chaos picked Khabib Nurmagomedov to beat the Diamond at UFC 242, and the relationship has been downhill ever since.

Poirier has gone onto become one of the leading lightweights in the UFC and has won praise for his outstanding charity work with The Good Fight Foundation, but Covington maintains that his old training partner is far from the 'honourable' person that is perceived.

'Dustin (Poirier) is not a nice, charitable guy,” Covington told MMAJunkie via BJPenn.com. “He is a piece of s*** person — let me show you this video.'

Covington then produces a video on his phone of Poirier in a sparring session before his fight with Nurmagomedov in which he allegedly goaded an amateur fighter. 

'Mike, so you can see it off-camera, I can’t show it on camera, look at this, look at this fight, this was at training. Wait, this is an amateur, by the way, no headgear, he was going training with him, watch. 

'Watch what he says in his face, "And New" — he’s rubbing it in the kid’s face after he drops him. What’s nice and honorable, and charitable about that?

'You just dropped an amateur who came to help you train for Khabib (Nurmagomedov) which — why are you training with amateurs when you’re preparing for Khabib as it is?' 

Referring to himself, Covington says Poirier failed to ask him to help prepare for the undefeated Dagestani. 

'You have the best wrestler, the best cardio freak in the gym as there is at the gym at the time, but you chose to train with amateurs and you’re supposed to be this good guy but you’re not and you’re knocking out amateurs, and you’re yelling in their face, ‘And New’. 

'That’s not Khabib kid, you didn’t just knock out Khabib. So Dustin’s a pr***. Dustin’s a piece of s***, and I’m sick of this, "nice guy" act.'

Covington previously accused Poirier of using his charity as 'a tax write off' claiming that 'he is conning the people with this so-called charity' and is 'the fakest guy in the world'.