Argentina boss Alejandro Sabella said Angel Di Maria would undergo tests on Sunday to determine the extent of the injury he sustained in his side's victory over Belgium.
Di Maria had to be substituted in the first half of Argentina's 1-0 win in Brasilia as a result of a thigh problem, but Sabella hopes he may be able to feature when Argentina return to action for Wednesday's semifinal.
"Angel has a problem in his right thigh and tomorrow he will have some tests and we will see," he said. "I hope that it won't be too [bad] in the case of Angel because Angel is vital to us."
Gonzalo Higuain, who scored the only goal of the game against Belgium, expressed hope the Real Madrid star would make a speedy recovery.
"He's a key player in this project," Higuain said. "I'm really sorry, but we hope that he will be ready as soon as possible because we know what he does for the team."
Information from the Associated Press was used in this report.