Defender Rafael Marquez trained on Monday with Mexico for the first time since injuring his right leg in last week's 2-1 friendly victory over Italy.
It was Mexico's first practice session with every player present since the team arrived in South Africa a few days ago.
Mexico opens the World Cup on Friday against host South Africa. Federation president Justino Compean said the squad "is nervous but confident" since Mexico has played more warm-up matches to prepare for the tournament than any of the other 31 teams.
Mexico has played 12 warm-up matches, winning eight, drawing two and losing two.
The main question seems to be the status of midfielder Andres Guardado, who has been relegated to a reserve role in recent matches after mostly being a starter since coach Javier Aguirre took over the team 14 months ago.
"I want to play and anyone who says he is happy on the bench is lying," Guardado said. "I'm ambitious and I want to show what I can do ... Not wanting to be on the bench is normal for any player who wants to win."
Aguirre has been giving more playing time recently to 37-year-old goalkeeper Oscar Perez after having mostly started Guillermo Ochoa, who is 13 years younger than his rival.
Mexico is loaded with young talent, particularly up front with Javier Hernandez, Carlos Vela and Giovani Dos Santos.
"I have no problem with Javier," Guardado said. "I respect him and if he thinks it's better others play, I will support them on and off the pitch."
The big question off the field is Mexico President Felipe Calderon. Will he attend the first match?
Calderon has been invited to attend the opening game by Aguirre and captain Gerardo Torrado. If he attends, he will be criticized at home for putting football ahead of more pressing problems like the increasing violence and killings related to drug-trafficking, and a slumping economy.
"With all respect, I don't want to offer an opinion," Compean said. "The president knows he is welcome, but this is a decision for the federal government."
