Despite their 6-1 Champions League hammering the Spaniard has hailed die Knappen as one of the best teams in Germany and is anticipating a tight game at the Allianz Arena
Die Knappen suffered an embarrassing 6-1 home defeat in the first leg of their Champions League last-16 tie with los Blancos on Wednesday night.
Guardiola, however, refuses to believe Schalke's continental collapse will have any bearing on Saturday evening's game at the Allianz Arena.
"The Bundesliga is a totally different competition," the former Barcelona coach told reporters. "I don't know what will happen tomorrow [Saturday]. But we've been training incredibly hard.
"Schalke are one of the best teams in the league. They've done very well so far.
"But we're in good form and can take one more step towards defending our title."
Bayern are currently 19 points clear at the top of the table, while Schalke, who are unbeaten in seven Bundesliga games, sit fourth.