Recent home defeats against Liverpool and Manchester City would suggest that David Moyes' men will find it almost impossible to get anything from the European champions this evening.
We are all waiting for the red half of Manchester to turn in that 'big' performance and remind everyone that they can still compete with Europe's elite.
However, it doesn't look promising. Moyes admitted in his press conference yesterday that United have defensive concerns and, if you look at the ease of which City passed through them during their 3-0 win, it is possible the game will be out of sight before the return leg in Munich next week.
Something has to change, though, and you just wonder whether Moyes is ready to turn to the approach that made his Everton team so difficult to beat during his ten years in charge at the club.
Marouane Fellaini was a key figure for Moyes at Goodison Park and it might be time for the giant midfielder to play further forward and support Wayne Rooney in attack.
One criticism of Moyes this season has been United's predictability. But if he insists on getting the ball wide then he may as well have one of the taller men on the field in the penalty area waiting to pounce.
Shinji Kagawa has found it tough going since his arrival from Borussia Dortmund too but has faced Bayern several times before and certainly wouldn't go into the game with any fear.
Playing Kagawa instead of someone like Antonio Valencia would send out the message that United are going to have a real go rather than be over cautious.
It's likely that the home side will switch to three in the centre of the park when Bayern have the ball in the hope of stifling the inevitable wave of attacks.
Pep Guardiola's men will score at some point so the task for United is to still be in the tie for the return leg. A 2-1 defeat wouldn't be a bad result and as we have seen in previous campaigns English teams have managed to pick up surprise results at the Allianz Arena.
At home the visitors have secured the Bundesliga title without losing a single game and they will certainly try and get the majority of the work done tonight before the second leg.
Players to watch
Alex Buttner - The Dutchman is in line to replace the suspended Patrice Evra. It's a daunting task for the youngster especially as he will come up against Arjen Robben, Franck Ribery or both at some point. It's vital that he is given protection to have any chance and if he can cope it may persuade the club not to spend millions in the summer on a replacement for the Frenchman.
Bastian Schweinsteiger - The midfield general is still only 29 and enjoying his peak years. He's the kind of player United have been crying out for since Roy Keane left and is as influential in the attacking third as he is defensively. Expect the German international to dictate the play from deeper later on and supply the bullets for Bayern's array of attacking talent.
Wayne Rooney - Will the real Wayne Rooney please stand up? He certainly has in the Premier League but has never quite set the Champions League on fire in the same way. Rooney's role will be pivotal this evening and he may well play far deeper than is normal to help reduce the space in front of the United defence.
Franck Ribery - The Frenchman was voted the third best player in the world behind Lionel Messi and Cristiano Ronaldo at the recent Ballon d'or ceremony. If he performs anywhere near the level he is capable then United's makeshift defence could have a night to forget. Capable through the middle or more probably from wide if he doesn't score tonight he's certain to have a hand in the build-up.
Bayern will win the game but United will put on a better show than many expect. A 2-1 defeat wouldn't be a disaster and, as Chelsea showed when they won the competition, performing poorly in the Premier League doesn't necessarily mean you can't succeed in Europe.