Polo Reyes can now return to the Octagon.

The UFC lightweight was handed a six-month suspension by USADA after he tested positive for the prohibited substance ostarine, the agency announced Monday. An investigation turned up that the drug got into Reyes’ system from a tainted supplement, which resulted in a reduced sanction.

Reyes’ six-month ban is retroactive to March 15, the day he was first provisionally suspended. That means the Mexican fighter is able to compete again right away.

“Following notification of his positive test, Reyes provided USADA with information about two dietary supplement products he was using at the time of the relevant sample collection,” USADA stated in a release. “Although no prohibited substances were listed on the supplement labels, testing conducted on independently sourced, unopened containers of the products by the WADA-accredited laboratory in Salt Lake City, Utah, indicated that they contained Ostarine.”

Ostarine is a selective androgen receptor modulator (SARM), which is sold illegally worldwide as a performance-enhancing drug. It has been found numerous times in supplements, though it was not on the label, including in multiple cases in the UFC, including Yoel Romero and Tim Means.

Reyes (8-4) is coming off a one-minute knockout of Matt Frevola at UFC St. Louis, which earned him a $50,000 Performance of the Night bonus. He has won four of his five fights in the UFC with the lone loss coming against contender James Vick. Reyes, 33, is a veteran of The Ultimate Fighter Latin America 2.