Manchester City striker Sergio Aguero is a doubt for Argentina's 2014 World Cup qualifying match with Bolivia this weekend after suffering a groin injury.
Aguero picked up the problem during training and has until this morning to prove his fitness.
The 23-year-old's injury is similar to the one that ruled him out of City's 4-1 victory over Aston Villa in the Premier League in October.
"Sergio Aguero has a sore groin and is doubtful for the match against Bolivia," Argentina coach Alejandro Sabella told the Argentinian Football Association's website.
"In the event that Aguero does not play, Javier Pastore may replace him."
Following the clash with Bolivia, Argentina will face Colombia in Barranquilla on Tuesday.