The Ultimate Fighting Championship has held two pay-per-view events in 2015, UFC 182 and UFC 183. The four fighters who headlined those fight cards, Jon Jones , Daniel Cormier , Anderson Silva and Nick Diaz , were subjected to out-of-competition drug tests prior to the events. All failed at least one test except for Cormier
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Daniel Cormier on UFC PED Users: ‘They Will Get Caught’ – MMA Weekly