Six UFC 146 Heavyweights Drug Tested At Random Following Tuesday's Press Conference

All six heavyweights in attendance at Tuesday's UFC 146 press conference at the MGM Grand resort in Las Vegas were administered random unexpected drug tests following the promotional affair. confirmed the news with Nevada State Athletic Commission Executive Director Keith Kizer on Wednesday.

The incident marks the first time fighters have been tested so far in advance from the event. Most drug screens — which test for recreational and performance enhancing drugs — are conducted days before events, with a second test following immediately after the fights.

Among the fighters tested on Tuesday were headliners Junior Dos Santos and Alistair Overeem, as well as co-main event fighters Cain Velasquez and Frank Mir. Main card standouts Roy Nelson and Antonio "Bigfoot" Silva were also tested on Tuesday.

UFC 146 takes place on May 26 at the MGM Grand Garden Arena in Las Vegas and marks the promotion's first all-heavyweight main card. In the headliner, recently-crowned champion Junior Dos Santos will look to defend his crown against ex-Strikeforce, DREAM and K-1 titleholder Alistair Overeem. In the co-main event, former champions meet as Cain Velasquez takes on Frank Mir in a number-one contender bout. Additionally, the main card also features Roy Nelson vs. Antonio Silva, Shane del Rosario vs. Gabriel Gonzaga and Mark Hunt vs. Stefan Struve.