Spain defender Michel Salgado is anxiously awaiting the result of tests on a hamstring injury he suffered during training on Tuesday.
The Real Madrid star has already been ruled out of Saturday's friendly against Russia and if the test results are not favourable, he could also miss the World Cup.
That would be a particularly cruel development for Salgado, who was forced to sit out Euro 2004 after picking up a similar injury during Spain's training camp for the tournament.
Team doctor Genaro Borras said: "My first impression is that there's no serious damage.
"The injury is in the same area where two years ago he sustained a more serious problem.
"In 48 hours we will have another test but I believe he could recover in five days."