The Bavarians are sixth in the league and all but out of the Champions League after Tuesday's 2-0 home defeat to Girondins Bordeaux, with pressure mounting on coach Louis van Gaal.
"I am sure this will be a tough match but it is possible to beat Bayern," Schalke striker Jefferson Farfan told his club website.
"Great clubs like Bayern who have such good players are always under pressure. We won't think about their problems and we will just focus on playing our game successfully," the Peruvian said.
"There is always a chance to beat Bayern. We will not hide in the back," said Magath, a former Bayern coach himself.
With Schalke strikers Kevin Kuranyi and Farfan in fine form having scored more than half of their team's goals so far and veteran Marcelo Bordon imperious in the back, the wounded Bavarians have their work cut out.
"The day off is for the heads to clear and turn to focus on Schalke," van Gaal told reporters. "This is a crucial match which we must win."
