In a development that could help Canelo Alvarez's reputation in the aftermath of a pair of failed drug tests and his removal from a May 5 pay-per-view rematch against Gennady Golovkin, the Mexican star submitted to hair follicle testing which came back negative. 

Nevada Athletic Commission executive director Bob Bennett, who made the request for the test, told ESPN on Thursday that Alvarez (49-1-2, 34 KOs) did not show any traces of the banned performance-enhancing drug clenbuterol. NAC collected hair samples on March 29 and testing was handled at the WADA-accredited Sports Medicine Research & Testing Laboratory in Salt Lake City, Utah. 

Because substances like clenbuterol are detectable in urine for less than a week after ingestion but can be found in hair for several months, the negative follicle test could support Alvarez's claim that his failed tests in Mexico on Feb. 17 and 20 for trace amounts were due to ingesting contaminated beef. 

Alvarez, 27, who knew he was facing a likely suspension, withdrew from the much-anticipated rematch on April 3, but maintained his innocence throughout. Two weeks later, he was suspended for six months by NAC retroactive to the date of his first test and wasn't fined because there wasn't a fight purse to pull from after Alvarez withdrew. 

"They found traces of clenbuterol in his system and if he was using it there would probably still be enough in his system that it would show up in his hair," Golden Boy Promotions CEO Oscar De La Hoya told ESPN. "We did the hair test to prove this was accidental. Canelo is telling the truth about the meat contamination and he went far and beyond what he had to do by agreeing to have this hair test done so he can keep on proving that he is an innocent fighter.

"Meat contamination is a problem in Mexico. It happened with the national soccer team and it has happened with several athletes in Mexico. I believe what Canelo wants to do now is keep proving until his career is over, 10 or 15 years from now, that he is a clean fighter and an innocent fighter and that he did not do this purposely whatsoever."

Golovkin (37-0-1, 33 KOs), the unified middleweight champion who settled for a controversial draw against Alvarez in their exciting first bout last September, will still fight on May 5 against former 154-pound title contender Vanes Martirosyan (36-3-1, 21 KOs) in Carson, California. 

Should Golovkin be victorious, in a fight that could move him into a tie with Bernard Hopkins for the most title defenses in middleweight history (20), a fall rematch with Alvarez could still be in place for Mexican Independence Day weekend in Las Vegas on Sept. 15. 

"We first have to see what happens with Golovkin on May 5 and then we'll take it from there, but Canelo will definitely fight in September," De La Hoya said. "Golovkin is the priority, but we don't know what will happen on May 5. But on our side, Canelo will fight in September."

Whether or not Alvarez knowingly ingested clenbuterol, his suspension was necessary due to NAC bylaws that claim a banned substance of any kind must lead to disciplinary action. The vote for his suspension passed unanimously on April 18 by a fight-member panel. 

"We initiated the test to be as comprehensive as possible but knowing it's very difficult, according to the experts," Bennett said. "It's a difficult process to be able to confirm whether there is clenbuterol in the hair follicles, but I talked to [SMRTL president and laboratory director] Dr. [Michael] Eichner and he said they'd run the test even though it is even more difficult to run on light-colored hair. But we sent them the samples and the tests came back negative."

De La Hoya said Alvarez is willing to submit as many random drug tests as VADA wants, despite the fact that Alvarez has been criticized for withdrawing from the VADA test program after the fight was canceled. 

"Canelo is willing to pay for the program," De La Hoya said. "He is willing to do whatever it takes to clear his name, including take a lie detector test. We're going to do one. He wants to prove he is a clean fighter."

Alvarez's hair follicle test was the first of its kind for NAC, which felt it was important to get as much information as possible about Alvarez's case given the magnitude of the rematch with Golovkin and the fact that Alvarez tested clean in March after moving his camp to the United States.