LAUSANNE, Switzerland (AP) -- The World Anti-Doping Agency says it will challenge the Mexico Football Federation for clearing five players of doping by accepting the claim that contaminated meat caused their positive tests for clenbuterol.
WADA said it appealed to the Court of Arbitration for Sport and would not comment further.
The five players tested positive for the banned anabolic agent at a May training camp before the Gold Cup.
Goalkeeper Guillermo Ochoa, defenders Edgar Duenas and Francisco Rodriguez, and midfielders Antonio Naelson and Christian Bermudez missed the tournament but were not punished.
WADA is also challenging 2010 Tour de France winner Alberto Contador at CAS, after he blamed contaminated meat for a clenbuterol positive.