Schalke v Augsburg
Suat Serdar underwent scans on a fibula injury after Schalke suffered a disappointing home defeat to Augsburg.
David Wagner believes psychological problems are to blame for Schalke's sluggish return to Bundesliga action, while Suat Serdar is facing another spell on the sidelines.
After falling to a resounding 4-0 defeat to Borussia Dortmund in the Revierderby last weekend, Schalke went down 3-0 at home to Augsburg.
Eduard Lowen's magnificent free-kick put Heiko Herrlich's side in front after six minutes and Noah Sarenren Bazee doubled its advantage in the second half, punishing some lacklustre defending from Salif Sane and Jonjoe Kenny.