Luke Rockhold doesn’t believe fighters should be allowed to use testosterone replacement therapy, even if it’s been prescribed and watched-over by medical personnel.

Rockhold, though, will have to face a fighter on TRT this Saturday when he meets Vitor Belfort at UFC on FX 8.

The former Strikeforce middleweight champion will be making his Octagon debut against Belfort in “The Phenom’s” native country of Brazil.

“I don’t necessarily trust him,” said Rockhold, during an interview with ESPN. “I don’t necessarily trust the system. Do I think he is cheating? Yes, I do. Do I care? Yes and no.”

Rockhold said he believes TRT can “help in some ways, but it can also hurt you. I think it gives you some explosiveness and it can give you strength.”

Belfort was allowed to use TRT prior to defeating Michael Bisping earlier this year. There has been much talk concerning this, as he failed a previous drug test in Nevada for steroids.

In the same interview, Rockhold’s trainer, Javier Mendez of American Kickboxing Academy, admitted that he uses TRT.

I wasn’t going to tell anyone this, but I will tell you. I am on TRT. I think its cheating. It gives you a slight advantage over the people who aren’t on it. The recovery time is much faster, and that means you can get back to training harder and you can train harder.

Does it concern you that someone so close to Rockhold – and the rest of AKA, which includes Cain Velasquez and Daniel Cormier – uses TRT?