Most UFC athletes publicly support USADA regularly on social media, in interviews and elsewhere, unquestioningly repeating their claims to be working for a clean sport. Junior dos Santos was one of them until he found himself on the wrong end of a positive test caused by a contaminated supplement from a source he had gone out of his way to verify was clean.
Dos Santos expressed his disappointment with how his case was handled by USADA in a fantastic, in-depth interview with Fernanda Prates at MMA Junkie, detailing how he was forced to sit out and spend significant amounts of money attempting to clear his name, only to still receive a suspension, despite great effort to avoid contaminated supplements.