“As part of a voluntary testing program that Francisco Vargas requested ahead of his June 4 fight, he tested positive for Clenbuterol.
“Francisco believes he tested positive due to ingesting contaminated meat in Mexico where clenbuterol is commonly used by ranchers in livestock feed. The Associated Press reported this week that this practice may impact athletes throughout the country ahead of the 2016 Olympics.
“Francisco has, is and will always be a clean fighter. That is why he insisted on this voluntary testing program ahead of the first defense of his WBC championship.
“He previously tested clean as part of this same voluntary testing regiment and in all of his previous fights.
“He will immediately leave Mexico to finish his training camp in the US in order to avoid any possible repeat of this situation and is fully cooperating with the California State Athletic Commission to submit to all required testing ahead of his June 4 title defense.”