Mexico's World Cup players are being banned from eating beef, a move aimed at avoiding positive doping tests from meat contaminated with the performance-enchancing drug clenbuterol.
Coach Miguel Herrera said Wednesday he had told his players more than a month ago not to eat red meat.
During the 2011 Gold Cup, five Mexico players tested positive for clenbuterol, a muscle-building drug. The Mexican Football Federation eventually cleared the players of doping. The World Anti-Doping Agency accepted what it termed "compelling evidence" that meat in Mexico was contaminated with clenbuterol and produced the positive tests.
Mexican authorities have acknowledged that the drug, which is banned in the sports world, has been used in the country to fatten cattle.