Jake Shields today admitted to taking a banned diuretic supplied by a friend prior to UFC 150.

Shields (30-7-1), 36, spoke to the Nevada State Athletic Commission via telephone while seeking a license to fight Brian Foster (22-6) at WSOF 17 on Saturday in Las Vegas. Fighters who are older than 35 are required to appear before the commission.

Shields was granted a conditional license pending the completion of his pre-fight medical paperwork, which lacks a clean MRI and hepatitis-B test. His fight headlines WSOF 17, which takes place at Planet Hollywood in Las Vegas. The main card airs on NBCSN following prelims on MMAjunkie.

Open records laws in Colorado prevented the state's athletic commission from disclosing the banned substance for which Shields tested positive following a victory over Ed Herman at UFC 150, which took place in Denver on Aug. 11, 2012.

Shields announced he had taken a banned substance and was suspended six months by the Colorado Department of Regulatory Agencies' Boxing Commission, which oversaw the event. But the fighter declined to give additional details about the substance, and the commission could not disclose it.

Speaking before the five-member commission, Shields today said he was given the substance by "someone I know through another fighter" and took it to help him cut weight for the fight, which initially was a win but later changed to a no-contest.

Asked to elaborate on the diuretic he took, Shields said, "I don't really know too much about it, to be honest.

"Obviously it was a mistake, and I served my suspension," he added.

Shields said he didn't remember whether he had been required to disclose any substances he was taking prior to the fight. In Nevada, pre-fight medical paperwork asks fighters to disclose any medications or substances they've taken in the previous two weeks.

"I learned from my mistakes," he said. "I definitely don't want to go through what I went through before."

Shields was also grilled about his role in an infamous brawl in 2010 under the now-defunct Strikeforce banner that led to a fine and 90-day suspension. Shields explained to the commission the circumstances surrounding the incident, which resulted in an in-cage melee between his camp and Jason "Mayhem" Millerz. The commission sought assurance that there would be no similar situation in Nevada.

Shields pledged not to run afoul of the NSAC. He said he would review the commission's list of banned substances and review the commission's policy on unsportsmanlike conduct.

Shields said he is in the process of getting his medical paperwork updated and will submit the necessary forms for licensure.

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