Record-breaking World Cup scorer Miroslav Klose backed misfiring Bayern Munich forward Thomas Mueller to rediscover the net-busting form that made him one of Europe's most feared strikers.

Bayern host Schalke on Saturday with a three-point lead in the Bundesliga but with German international Mueller struggling badly in front of goal.

Mueller, 27, hit 20 goals in Germany's top flight last season but has just one in 15 league games this term.

He was substituted after 70 minutes of last Saturday's 2-1 win over Werder Bremen after failing to manage a shot on goal.

Ex-Bayern and Germany team-mate Klose says Mueller has lost the unconventional touch which made him so dangerous and advised him to rethink his game.

"What stands out for me is that he always wants to be in a position in the penalty area where he only has to shoot the ball a metre to score," Klose told Kicker.

"He knows he has to follow seemingly lost causes and chase the ball."

The 38-year-old Klose became a member of Germany's coaching staff in November and retired last season having set the all-time record with 16 goals at World Cup finals when die Mannschaft won the 2014 edition in Brazil.

He says Mueller must keep working hard and the goals will flow again.

"You're always thinking about it and you can't let yourself go crazy, which isn't easy, because you want to score with all your might," said Klose.

"You carry it with you when things don't work. I know Thomas, he will learn from this phase and make it work."

Goals or no goals, Mueller's work up front is priceless, according to his Bayern team-mate Douglas Costa.

"He helps us in a lot of situations and creates space so he is very important for us," the Brazil winger told Bild.

"We'll find a solution together. When he's happy, then we're happy and I'm sure he will score again soon."