Canelo Alvarez submitted two positive samples for the banned substance clenbuterol, and although his promoter cited one expert saying it could be an innocent case of eating contaminated meat in Mexico, the head of the Nevada Athletic Commission will investigate further in advance of Alvarez's May 5 rematch against Gennady Golovkin in Las Vegas.
Alvarez's promoter, Golden Boy Promotions, said it was notified of "trace levels" of the drug in Alvarez's sample and will move the Mexican boxer's training camp to the United States.
"I am an athlete who respects the sport and this surprises me and bothers me because it had never happened to me," Alvarez said in a statement released Monday. "I will submit to all the tests that require me to clarify this embarrassing situation and I trust that at the end the truth will prevail."
Golden Boy said it shared the findings with Tom Loeffler, the promoter for Golovkin. Loeffler told the Los Angeles Times he wants the Nevada Athletic Commission and the three sanctioning bodies to review the findings at the World Anti-Doping Agency lab.
"Gennady has always wanted a level playing field so no one would question his own punching power, and we're happy that testing is in place for this fight," Loeffler said.
Bob Bennett, the executive director of the Nevada Athletic Commission, said it's "premature" to make a ruling on Alvarez's test results.
"We have received the adverse analytical finding from Mr. Alvarez and per our standards will be conducting a full investigation," Bennett told The Times.
Former super-featherweight champion Francisco Vargas was cleared to fight in California two years ago after submitting a positive test for clenbuterol that was later ruled to be connected to his consumption of tainted meat in Mexico. Recent International Boxing Hall of Fame inductee Erik Morales also tested positive for clenbuterol but was cleared to fight in New York.
Clenbuterol is used by some farmers to increase the appetite of their cattle.
Alvarez submitted his positive samples on Feb. 17 and 20, according to an official unauthorized to comment publicly.
Alvarez, a former two-division world champion, and three-belt unbeaten middleweight champion Golovkin fought to a draw in September at T-Mobile Arena. The rematch was finalized last month.
Alvarez has said he expects to train again in San Diego, but will consider some high-altitude sessions in Big Bear, where Golovkin is training.
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8:00 p.m.: This article has been updated with additional information.
3:05 p.m.: This article has been updated to add a statement from Nevada Athletic Commission executive director Bob Bennett.