France captain Patrick Vieira has set himself a Sunday deadline to prove his fitness for Euro 2008.
The Internazionale midfielder has already been ruled out of Les Blues' opening Group C fixture against Romania on Monday with a thigh problem.
France coach Raymond Domenech has placed former Arsenal and now AC Milan midfielder Mathieu Flamini on standby should Vieira's injury fail to respond to treatment.
Meanwhile, Vieira has given himself until the end of the week to prove his fitness after reporting a "little tear" in his thigh muscle.
He said: "It is nothing serious, but unfortunately it has happened at a bad time because every day counts now and the tournament is approaching.
"Now, what I have to do is try to recover as quickly as possible.
"If by the end of the week I am not training with the squad, that would mean I will not be participating in the Euros.
"But I am still optimistic."