Italy and Juventus goalkeeper Gianluigi Buffon is a doubt for the defending champions' next World Cup match after hurting his back in their 1-1 draw with Paraguay.
The 32-year-old was replaced at half-time by Federico Marchetti and coach Marcello Lippi said it was too early to tell how bad it was.
"He has a bit of problem in his back," said Lippi. "He had an ache during the warm-up and then he said he wanted to play, but after the first half he said he couldn't continue.
"It's unfortunate as we lost a substitution which would have been handy for the game. I don't know how bad the injury is or how long it will take him to recover. The doctors will have to tell us that."
Buffon came into the World Cup on the back of a poor season with Juventus where he missed chunks of the season due to injury.
But he is widely regarded as one of the standout keepers of the modern era and kept five clean sheets and conceded just two goals in Italy's run to the World Cup title in 2006.
Italy's next match is against New Zealand on Sunday.