02/05/2015 07:00 EST | Updated 04/07/2015 05:59 EDT

UFC paid for out-of-competition drug test that busted MMA star Anderson Silva

TORONTO - The cost of seeing MMA icon Anderson Silva swallowed up in a doping scandal is probably incalculable to the UFC.

But the executive director of the Nevada State Athletic Commission says it's to the UFC's credit that the organization paid the freight for the out-of-competition test that caught the former middleweight champion.

"I will tell you that the UFC has aggressively gone after their own fighters that are using performance-enhancing drugs," said Bob Bennett.

"The UFC has provided the financial means for us to do this out-of-competition testing ... Not only does the UFC pay for us to do it, then they lose some of their top fighters that we catch," he added. "So I think it's a real credit to the UFC that they're trying to level the playing field or level the Octagon."

Silva, who has denied cheating, tested positive for two steroids at a Jan. 9 test in California. Coincidentally Nick Diaz, whom Silva beat in the main event of UFC 183 last Saturday in Las Vegas, tested positive fight night for a third time for marijuana.

Both men have been temporarily suspended pending a hearing.

The Nevada commission, seen as the leader in combat sports commissions, tests fighters out of competition and at events. It follows the World Anti-Doping Commission protocol and has sent representatives as far afield as Argentina to test fighters on the promoter's dime.

Out-of-competition tests are random. "Nobody knows when we're coming, what day, whatever. We don't discuss it with anyone," said Bennett.

Such tests are only for performance-enhancing drugs, including steroids and diuretics. Blood and urine samples are sent to the WADA-accredited Sports Medicine Research and Testing Laboratory in Salt Lake City.

On fight night, samples are also taken. Bennett says most fighters on a card are tested pre- and post-event for performance-enhancing and illicit drugs.

Who is chosen fight night is random and not everyone is tested due to cost. But most are, said Bennett.

Bennett says the headliners are tested "most of the time" out of competition. He acknowledges it is not all-encompassing but says "at least it levels the playing field and lets the fighters and the promoters know that we have a pretty intensive performance-enhancing drug policy, even though there's always room for improvement."

While Diaz has a medical marijuana card issued in California to treat anxiety, Bennett says that doesn't mean a green light in Nevada. A fighter can ask for a therapeutic use exemption for health issues but that probably wouldn't work given other options to treat anxiety disorders.

That may change down the line, with the drug decriminalized in several states, he added.

Bennett says the Silva camp had asked for the 'B' sample from the out-of-competition test to be checked at another lab. But according to WADA, the 'B' sample can only be checked by the same lab, essentially to preserve chain of custody.

The Silva camp could do that, including having a representative on site to watch.

Bennett is a retired FBI special agent and U.S. Marine captain who previously served as a pro boxing judge for the Nevada commission.

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