Czech Republic striker Milan Baros is uncertain whether he will overcome his foot injury in time to play in the World Cup finals.
Baros was the winner of the Golden Boot at Euro 2004
The 24-year-old suffered the injury in a World Cup warm-up against Trinidad and Tobago on 3 June.
The Aston Villa forward tried to train after taking pain-killing injections, but only lasted 30 minutes.
"The treatment has not been going in the way we had planned," said team spokesman Lukas Fousek.
Baros had been hopeful of facing Ghana in Cologne on Saturday, but his wait looks set to continue after breaking down in training.
He added: "It was OK for a while, but then I had to stop. When I make a faster movement, it hurts.
"I hoped it would get better, but it returned again. I have to keep waiting."
The Czech Republic, who were 3-0 winners in their opening Group E game against the United States, are rapidly running out of options up front.
Giant striker Jan Koller was forced off early against the USA with a thigh injury.
The 33-year-old Koller has only stretched the muscle and could return by the knock-out stages, providing the Czechs progress.
Midfielder Vladimir Smicer was also ruled out of the tournament because of a hamstring injury.