Schalke may look to draft in former Germany goalkeeper Timo Hildebrand after Ralk Fahrmann ruptured knee ligaments in the Bundesliga on Saturday.
Schalke's first-choice shot-stopper suffered the cruciate injury when he conceded a penalty in the 2-1 defeat to Kaiserslautern.
The 23-year-old was shown a red card but that will be of little consequence to him as he faces a significant spell out with the injury.
"Ralf will miss at least three months," Schalke general manager Horst Heldt told bild.de.
The club must decide whether Fahrmann requires surgery and are reportedly now looking to a possible replacement.
Hildebrand is currently with second division club Eintracht Frankfurt but a move to Schalke appears likely. His agent Jorg Neblung said he expects the move to happen this week.
"When Timo joins a club he wants to be sure that he plays," he said.