Following a number of reports and rumors, Marc Ramondi of MMAFighting.com confirmed the banned substances that both Brock Lesnar and Jon Jones took that resulted in their ongoing issues with USADA.
Lesnar, who tested positive in both out-of-competition and in-competition tests for his UFC 200 bout with Mark Hunt, tested positive for hydroxy-clomiphene. The news was first made public by ESPN and The L.A. Times, before later being confirmed by MMA Fighting.
Jones, who was scheduled to headline UFC 200 in a 205-pound title unification bout against Daniel Cormier, was pulled from the event when he tested positive for two banned substances in an out-of-competition test.
According to the MMA Fighting report, Jones also tested positive for clomiphene, an anti-estrogen agent, as well as Letrozole, aromatase inhibitor.
Due to the proximity of the positive tests to the UFC 200 date, which was sanctioned by the Nevada Athletic Commission (NAC), both Lesnar and Jones face potential repercussions from USADA and the NAC. They will not, however, face fines from the UFC.