Chelsea midfielder N'Golo Kante is facing an extended spell on the sidelines.
Kante played 84 minutes against Tottenham on Sunday before being forced off with the injury.
In his absence, the Blues conceded an injury-time goal from Harry Kane to draw the game 2-2.
The Telegraph says Kante is expected to miss at least three to four weeks with the injury, but more will be known once he received the results of an MRI scan.
Blues management will be hoping he will be back for their clash with Liverpool on September 18.