A leading Mexican football director said that a dressing-room row rather than tiredness may have been behind the decision of three top players to miss the Copa America.
"I hope we get the truth and transparency as to what happened in the dressing-room and what caused the three players to leave the squad, because they were not tired," Jorge Vergara told reporters.
"Something happened, I don't know what it was, and we will see in the report," added Vergara, who is a member of the Mexican Football Federation's (FMF) national team committee and president of Guadalajara, the country's most popular club.
"Sincerely, I believe there were problems in the dressing-room," added the outspoken director.
Defenders Carlos Salcido and Ricardo Osorio and midfielder Pavel Pardo all pulled out of the Copa America squad less than a week before the tournament was due to begin in Venezuela
The European-based trio, however, had played in the CONCACAF Gold Cup in the United States.
Mexican media say the three players are all loyal to previous coach Ricardo La Volpe, a bitter personal rival of current coach Hugo Sanchez, and there has been widespread speculation of a split in the squad.
Most commentators agreed that the team performed better without them at the Copa, where Mexico beat Brazil 2-0 on the way to reaching the semifinals.
Earlier, Mexico had been criticized for its displays at the Gold Cup, despite reaching the final where it lost to old rivals United States.
FMF president Justino Compean said he stood by Salcido, Osorio and Pardo.
"We have to understand that these players have commitments with their clubs, that they play in very tough competitions in Europe... and they need to have a rest," he said.