Anderson Silva, 42, one of UFC's greatest fighters, tested positive for a banned substance for the second time in an out-of-competition test taken on October 26th.
The UFC reported today that they were notified by USADA about the test failure and the provisional suspension.
Silva was scheduled to headline the company's November 25th show in Shanghai, China, against Kelvin Gastelum. UFC officials said they were looking for a new opponent for Gastelum.
This was the second time Silva has failed a test.
Silva tested positive for four banned substances, steroids Drostanolone and Androsterone, as well as anxiety medications Oxezepam and Tamazepam on January 31st, 2015, the date of his five-round decision win over Nick Diaz.
He claimed the anxiety medications were due to problems sleeping and the steroids were unknowingly a part of a pill he had gotten from Thailand to improve sexual performance.
The substance he tested positive in the latest failure won't be publicly revealed until he goes through his hearing process and final discipline is decided on.