The Nevada State Athletic Commission on Monday handed down a five-year ban to UFC welterweight Nick Diaz after he allegedly tested positive for marijuana following his fight against Anderson Silva at UFC 183 in January.

Diaz was also fined 33 percent of his total purse worth $500,000, which comes to $165,000. Diaz also faces additional financial penalties to reimburse the cost of his suit incurred by the state.

Diaz appeared at the hearing with his attorney Lucas Middlebrook, who presented an aggressive defense that questioned the validity of the test results. The test showed that the fighter had elevated levels of marijuana in his system just minutes after his bout against Silva ended.

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After the hearing concluded, Diaz spoke to reporters outside while expressing his extreme disappointment in the commission's decision. He didn't mince words.

"I'm pretty pissed off," Diaz told FOX Sports. "I got into this sport for this exact reason being stuck in a room like that with people like that. First of all, this sport, this commission, they've done everything they can to keep me from being all the way on top where I should be. They've done everything they could to keep me from proving to the world that I'm the best fighter in the world, which I am. They want to have nothing but weak sauce fighters in the sport.

"Those people are nothing but a bunch of crooks up there."

During the hearing, Middlebrook argued that two separate tests were conducted by the Sports Medicine Research & Testing Laboratory (SMRTL) -- a World Anti-Doping Agency-accredited lab -- before and after his fight, with both results showing Diaz well under the 150ng/ML limit for marijuana. The lone positive test came back from Quest Diagnostics, which showed Diaz with over 700ng/ML of marijuana.

Diaz's attorney vehemently disagreed with the test results while also calling upon an expert witness to testify to the validity of the testing and how the three separate amounts proved the lone positive was actually false.

The commission consistently fired back while also pointing out that Diaz did not claim his use of marijuana on a pre-fight questionnaire, which all athletes are required to sign and date before a contest.

Once testimony was completed, Middlebrook fired off another salvo at the commission, which is a governing body overseeing athletics in the state but not an actual court system with a judge and jury setting legal precedent.

"With all due respect, if the commission imposes discipline based on the complaint as written, which wholly ignores the two negative tests, thereby depriving this man of his earnings and his future ability to earn a living, it's not only the highest form of administrative abuse of discretion, but it's ripe for judicial review and reversal," Middlebrook stated.

When Diaz finally took his place at the table in front of the commission, he chose not to respond to any questions and instead pleaded the Fifth Amendment for every answer. Commissioner Pat Lundvall continued to press Diaz with questions and he responded by pleading the fifth repeatedly.

"Respectfully, I'm not going to answer the question," Diaz stated. "Fifth Amendment."

Following the three hour-plus hearing, the commission finally went into deliberation, where Diaz was subject to the heavy fine while Lundvall suggested a lifetime ban for him in the state of Nevada.

Eventually the commission opted for a lesser sentence of five years while also stating that at this stage of Diaz's career -- he's already 32 years old -- that would likely be a lifetime ban as well.

The commissioners stated that their decision to suspend Diaz wasn't as much about his use of marijuana but his disregard for their rules and regulations after he was already suspended for the same drug in 2007 and 2012.

"This not just a case of marijuana," Chairman Francisco Aguilar said. "I think this is a case of complete lack of disregard for the sport."

The commission voted unanimously on the verdict with Diaz suspended for five years from the date of his fight against Anderson Silva, which would make him eligible to return to action on Jan. 31, 2020.

Diaz immediately got up from his seat and left the room when the hearing was finished. It's likely Diaz's attorney will file an appeal with the state for an additional hearing to be held at a later date.