Schalke manager Jens Keller is worried about the health of Kevin-Prince Boateng ahead of their Bundelisga derby against Borussia Dortmund on Saturday.
The 26-year-old played through the pain barrier after lasting 70 minutes on the pitch as the German side lost 3-0 at home to Chelsea in the Uefa Champions League on Tuesday.
The Ghanaian international is now racing to be fully fit after he struggled in the game against the Blues.
Schalke manager Jens Keller has revealed he is unsure about risking him against their rivals.
“”He has not trained a few weeks, is not in top condition. At half-time he told me that it is flat and can only play a quarter of an hour. ” Keller said
Boateng has played eight out of ten official matches so far this season.