Silva, Diaz both failed UFC 183 drug tests

Anderson Silva. (Felipe Dana/AP)

Just days after Anderson Silva won a unanimous decision over Nick Diaz in the UFC 183 main event in Las Vegas, it was revealed both men failed drug tests.

The UFC confirmed Tuesday night that Silva tested positive for the anabolic steroid drostanolone in a pre-fight drug test administered by the Nevada State Athletic Commission (NSAC) Jan. 9 and Diaz failed a post-fight test for having elevated levels of marijuana metabolites in his system.

Although Silva tested positive for a banned substance before the event, he was allowed to compete at UFC 183 because the NSAC reportedly didn’t receive the Jan. 9 test results until Tuesday.

The UFC released the following statement on Silva:

“On February 3, 2015, the UFC organization was notified by the Nevada State Athletic Commission that Anderson Silva tested positive for Drostanolone metabolites on his Jan. 9 out of competition drug test. UFC’s understanding is that further testing will be conducted by the Commission to confirm these preliminary results.

“Anderson Silva has been an amazing champion and a true ambassador of the sport of mixed martial arts and the UFC, in Brazil as well as around the world. UFC is disappointed to learn of these initial results.

"The UFC has a strict, consistent policy against the use of any illegal and/or performance enhancing drugs, stimulants or masking agents by its athletes."

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Silva had never previously failed a drug test in his nine-year UFC career. In an October interview with MMAJunkie, Silva spoke out against fighters that use steroids.

“People around the world love the UFC, but the kids love the UFC, and the families love UFC. It’s bad for the sport. I don’t think this is good because the sport can change the lives of the kids and the people in the world," Silva said. “When the guys test for the steroids, it’s bad because this is a problem. It’s bad not just for the UFC, but for the sport...

“When the guys test for the steroids, (they should have) no more fights. When you use the steroids, you use them for a long time. When you use the steroids for a long time, you have a problem. It’s a drug and it’s not good for the sport.”

It's unknown at this time what type of punishment the 39-year-old Brazilian will face and it's unclear if we'll ever see him compete inside the Octagon again. Silva said at the UFC 183 post-fight press conference he needed to go back home and discuss his future with his family before deciding if he'd ever fight again.

Meanwhile, this is the third time Diaz has failed a drug test for marijuana in the state of Nevada. He was suspended six months by the NSAC in 2007 after his fight with Takanori Gomi at PRIDE 33 then was suspended one year in 2012 after his loss to Carlos Condit at UFC 143.

The UFC released this statement regarding Diaz's failed test:

"The UFC has been notified by the Nevada State Athletic Commission that Nick Diaz has tested positive for marijuana metabolites following his fight with Anderson Silva at UFC 183 on Jan. 31 in Las Vegas, Nev. The UFC has a strict, consistent policy against the use of any illegal and/or performance enhancing drugs, stimulants or masking agents by our athletes. As a result of his positive test, Diaz has been informed that he has violated the UFC Fighter Conduct Policy and Promotional Agreement with Zuffa, LLC. The UFC organization will fully respect the Commission’s final decision relating to Diaz at a disciplinary hearing set for February 17."

Heading into UFC 183, Silva hadn't competed since breaking his leg in gruesome fashion at UFC 168 in December 2013. Diaz hadn't fought since losing to Georges St-Pierre at UFC 158 in March 2013.