Bayer Leverkusen could be without Hans Sarpei for two weeks after the Ghana international suffered a groin strain in the 1-1 draw with Schalke.
The 31-year-old had to be substituted midway through the first half after suffering the injury.
Sarpei is out of Ghana's team to play Morocco and Saudi Arabia
He is also already a doubt Bayer's UEFA Cup first round first leg clash with UD Leiria later this month.
Sarpei moved to Levekusen from Wolfsburg in the summer.