The Spanish giants come to Munich's Allianz Arena on Tuesday holding a 1-0 lead from the first leg, when Bayern failed to score in Madrid despite dominating possession.

The German media have criticised Pep Guardiola's side after a string of below-par and lacklustre performances since winning the Bundesliga title last month with a record seven games to spare.

However, Bayern twice came from behind to seal a 5-2 league win at home to Werder Bremen on Saturday and Mueller said the Bavarians now need all the support they can get.

"I don't want to go into today's game, all that counts for us is Tuesday," said Mueller on Saturday as Bayern bid to reach their fourth Champions League final in five seasons.

"Until then, we need full support from everyone around the club, especially from the media and press.

"We are all German. If we don't make it on Tuesday, then as far as I am concerned you can take us apart, but before that we need support."

The flattering scoreline against Bremen failed to mask Bayern's woeful first-half defending, which sounded the alarm bells for coach Pep Guardiola given the danger of conceding an away goal to Real.

- Bayern disappoint Guardiola -

Bayern have conceded the first goal in seven of their nine matches since winning the Bundesliga title late last month with a record seven matches to spare.

Once again the Munich defence was left wanting in the first 45 minutes before the reigning European champions roared back.

"That is the first time that I have been a bit disappointed and sad about the first half -- the fans didn't deserve that," said Guardiola.

"We were better in the second half, that's good for the mood ahead of the Madrid match, but it will be a completely different game.

"I trust my team and I hope that we can all manage it together."

Bayern blasted Werder 7-0 in Bremen last December, but Czech defender Theodor Gebre Selassie fired the visitors into a 1-0 lead after 10 minutes at the Allianz Arena.

France winger Franck Ribery equalised before Aaron Hunt capitalised on some poor marking for Bremen's second to make it 2-1 at the break.

Bayern equalised again when Mueller headed on Ribery's corner and Claudio Pizarro was on hand to stab home his shot to make it 2-2 on 54 minutes, then the Peru veteran added his second against his old club four minutes later.

Bastian Schweinsteiger then powered home a header on 61 minutes before Netherlands winger Arjen Robben hit the top corner of the net to make it 5-2 on 74 minutes, less than 60 seconds after coming off the bench.

Ribery has come in for criticism after several below-par performances, but Bayern captain Philipp Lahm backed the Frenchman for Tuesday's Real clash.

"I have no concerns about Franck and I am convinced he'll put in an outstanding display on Tuesday -- to help put us in the final," said Lahm.

"I'm happy with how we've played, it's much more fun when we're in control."