BERLIN (Reuters) -- Schalke 04 goalkeeper Ralf Faehrmann is doubtful for their Europa League group opener against Romania's Steaua Bucharest on Thursday after tearing ligaments in his right ankle during Sunday's 2-1 defeat to VfL Wolfsburg, the club said.

"Ahead of Thursday's game against Steaua and the weekend league match against Bayern Munich, the medical staff and the keeper are working together full-time so the 22-year-old keeper can return to goal in time" Schalke said.

Faehrmann was injured without the involvement of another player. His injury means Lars Unnerstall, 21, who has been moved up to second choice ahead of more experienced 35-year-old Mathias Schober, could be his replacement if he is not fit in time for those games.

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