Juventus are sweating over the fitness of Claudio Marchisio ahead of this weekend's Derby d'Italia against Inter.
The Italy international midfield "overworked" his left adductor muscle in Saturday's 3-1 win over Cagliari.
He underwent a series of tests yesterday to ascertain the severity of the injury.
Juventus' medical staff hopes to recover Marchisio in three or four days' time, but the doubt remains.
Inter have suffered a blow of their own in the last 24 hours with the news that Diego Milito could be out for as long as a month.