Nate Diaz came out with a statement on Thursday, claiming the UFC has informed him of having “elevated levels.” The Stockton-native, known for being vocal against PED’s, seemed furious about the idea he would ever have an adverse test.

Diaz didn’t mention a substance on his lengthy statement, but ESPN reports that he tested positive for “trace amounts of a prohibited selective androgen receptor module (SARM).”

This is what USADA has to say about SARMs, which have been banned by WADA since 2008:

“SARMs have the potential to be misused for performance enhancement in sport due to their anabolic properties as well as ability to stimulate androgen receptors in muscle and bone. They are currently prohibited at-all-times in the category of “other anabolic agents” under section S1.2 of the WADA Prohibited List. Some examples of SARMs are Ostarine and Andarine.”

It is worth noting that if this was from Ostarine, multiple fighters (like Sean O’Malley) have eventually received reduced sentences as the results were were consistent with supplement contamination. Diaz though, doesn’t even like the idea that this could have come from a tainted supplement, as he says he only takes “Whole Food or natural food supplements” and doesn’t even eat meat.

The report also states that Diaz has not been provisionally suspended for UFC 244, so as of this writing, the fight with Jorge Masvidal is still officially on. Diaz wanting to compete though, is a different matter. The 34-year-old initially stated that he has no intention of competing “until UFC, USADA or whoever is F—KING with me fixes it.”