Leyton Orient are waiting to discover the extent of the hamstring injury suffered by Kevin Lisbie.
The nine-goal striker pulled up during the second half of Tuesday night's victory over Yeovil in the Johnstone's Paint Trophy.
Lisbie is now a major doubt for Saturday's visit of Crewe, with boss Russell Slade keeping his fingers crossed the damage is not too severe.
"I've no idea on Kevin yet," said Slade.
"He's got a hamstring problem but we don't know how long that's going to be (that he is sidelined) or what the damage is at this stage."