Cody Garbrandt and TJ Dillashaw will coach against each other before battling at UFC 213
Garbrandt and Dillashaw are each coaching a team on the 25th season of UFC's reality TV show The Ultimate Fighter, the latest series of which will air for the first time tonight.
The pair used to be team-mates, training together as part of the Team Alpha Male collective, but are now bitter rivals after Dillashaw ditched the gym to join MusclePharm in Denver.
"Things went south when Duane [Ludwig] left Team Alpha Male and TJ started doing part-camps here," Garbrandt said.
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"He lied to the team about his involvement with the MusclePharm team.
"He sold out.
"I was always defending TJ but I lost a lot of respect for him over his disloyalty to the team and the people that helped him."
Garbrandt and Dillashaw will not only clash as coaches this year.
The UFC Bantamweight Championship, which Garbrandt spectacularly won from Dominick Cruz in December, will be on the line when the two fighters headline UFC 213 on July 8.
"TJ is a worthy opponent to showcase my skills against and I finally get to show that I am the superior fighter and athlete this summer," Garbrandt added.
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"There are some unresolved issues between us."
But even with such a big fight to train for, Garbrandt is delighted to have the chance to flex his coaching muscles for the first time.
"I was very excited for the opportunity," he said.
"I sat down with my coaches and asked if they would like to be part of it and they were all for it and wanted to help out because obviously I'm an athlete not a coach.
"It's nice to see what they go through daily in terms of training 50 or 60 fighters."