Schalke's central defender, Joël Matip has been ruled out for two weeks with a hamstring injury, sustained during this Saturday's 1-1 draw with Werder Bremen at the Veltins Arena.
The Cameroonian defender will miss this weekend's highly anticipated Revierderby against Borussia Dortmund at Signal Iduna Park, as well as the visit of Markus Gisdol's Hoffenheim to Gelsenkirchen.
It's unknown whether the product of the Schalke youth academy will be back for the return leg of Roberto di Matteo's side last 16 tie in the Champions League against Real Madrid; die Königsblauen trail 2-0 heading into the game at the Bernabeu.
Matip had previously stared in Schalke's victory against die Schwarzgelben early in the season, grabbing the first goal in a 2-1 victory for the die Königsblauen.
He has played a big part in the Rückrunde so far for di Matteo's side, appearing in every game since the Winter Break. The injury to Matip just adds to the problems faced by di Matteo, as Schalke are currently without eight senior players.