Star striker Oribe Peralta and promising youngster Rodolfo Pizarro will return to Mexico after picking up injuries on Sunday in El Tri's 5-1 victory over Fiji in the second round of games in Group C of the Olympic men's football tournament.
Club America's Peralta completed the game despite picking up a fractured bone in his nose, while Pachuca's Pizarro fractured his right fibula and was taken off in the 35th minute, announced the Mexican federation (FMF) in separate statements. Both players will be replaced, added the FMF.
Mexico is defending the Olympic title in men's football at Rio 2016 and drew 2-2 in its opening game against Germany, before Sunday's victory, in which Fiji was winning at half-time.
El Tri face a crucial match on Wednesday in Brasilia against Korea Republic and will likely have to earn the three points if it is to advance to the quarterfinals.
Peralta was the hero for Mexico four years ago at London 2012, when Mexico won its first gold medal in football and opened the scoring against Germany in El Tri's first game at the Rio Olympics.
"The news about Pizarro and Oribe after their respective examinations are unexpected and sad," tweeted Mexico's Olympic coach Raul Gutierrez. "We will analyze the best solutions."
"This makes us stronger," added Mexico center-back Carlos Salcedo.
The FMF has confirmed that Raul Lopez (Pachuca) and Carlos Fierro (Queretaro) will replace the injured stars.