1) Dante's Absence
Whilst it would be foolish to criticise a defence that has conceded just 15 league goals this season, it is clear that Brazilian defender Dante has been a key factor behind such miserliness. The central-half, who signed an extension to his contract last week, must be one of Europe's most improved performers over the last three years and has usually been the senior member of a partnership alongside either Javi Martinez (when fit) or Jerome Boateng. Even considering Dante's presence, Bayern have kept just one clean sheet in their last seven matches.
However, Dante is suspended for the first leg at Old Trafford after picking up his third booking in the competition against Arsenal last month, leaving Pep Guardiola with three options. Boateng and Martinez could be picked as a pair, something attempted by Bayern recently during their match away at Mainz, when they often looked shaky defensively (as much as Bayern ever do). Alternatively, Philip Lahm could drop in to a central defensive role, with Martinez taking over Lahm's now familiar holding midfield role.
The third option is to pick Daniel Van Buyten at the back, and the 36-year-old was paired with Dante for the weekend fixture against Hoffenheim. Given that Bayern conceded three times in a 3-3 draw, David Moyes may be crossing his fingers that Van Buyten gets a second chance.
Whatever the answer, Dante's absence gives United a genuine weakness to attempt to exploit in a line-up that otherwise provides very little cause for optimism. The obvious advice would be to start the match quickly with the intention of testing the central defensive pair early in the game.
2) European Adventure
It hasn't exactly been difficult to better their rotten domestic displays, but there is little doubt that Manchester United's best performances this season have come in the Champions League. A record of five wins and two draws in eight matches indicates a sharp improvement on their pitiful Premier League showings, and should provide a modicum of comfort to supporters.
What's more, the best display by far from United under Moyes came against German opposition, a 5-0 routing of Bayer Leverkusen in the BayArena.Coincidentally, this was also the last ground at which Bayern dropped league points before Saturday.
That night, Wayne Rooney was the star of the show as United were forced to perform without an injured Robin van Persie. He had a hand in four of the goals and operated as the lone centre-forward in front of a trio of Shinji Kagawa, Antonio Valencia and Nani. With Van Persie again injured (and Juan Mata ineligible), David Moyes has the option of attempting to recreate that formation by replacing at least one of those three with Danny Welbeck or Adnan Januzaj (we would suggest the former).
Another dominating presence that night was a certain Ryan Giggs, who played a significant part in the victory over Olympiakos before then being omitted from United's squad entirely for three of the four matches since, and left as an unused sub against Aston Villa this weekend.
So, does Moyes again turn to his old man in midfield with the hope of playing another couple of sumptuous passes to Rooney? Why the hell not, would be this writer's opinion.
3) Bayern's Struggles Against English Teams
Given that this is a side that have gone 53 Bundesliga matches without defeat, dropping just eight points in their last 45 domestic matches, it seems unlikely that form should play in any part in a positive spin on the tie as far as United are concerned, but there is one chink in Bayern's armour - their form against English sides.
In the last 18 months alone, Manchester City and Arsenal have beaten Bayern, whilst Chelsea (and Arsenal again) have drawn matches against the same opposition. In fact, of their last 11 matches against English opposition, Bayern have won just four, also losing four and drawing three.
Now I'm not suggesting that this is foolproof evidence. Bayern got past Arsenal in each of their last two seasons, their home defeat to City came in a match that was approaching meaningless for the German side and they beat Chelsea on penalties following the Super Cup 'draw'. But give me a break, I'm looking for positives here.
Given that Bayern's last three home games against English teams have ended in two defeats and a draw, if United could somehow take a lead (or even a draw) to the Allianz Arena then all should not be lost. They need only to look to the example set by James Milner and co in December, and that night remained the only time in the last three years that Bayern have conceded more than twice at home in any competition before Saturday's second-string line-up drew 3-3 - United have done it twice in two weeks.
Finally, despite their two-goal victory at the Emirates last month, it is important to note that until Wojciech Szczesny's red card, Bayern did not dominate Arsenal, and would have fallen behind had Mesut Ozil's penalty been of better quality. United have taken four points from Arsene Wenger's side this season, and so the mantra must be that if Arsenal can lose 3-1 on aggregate after playing for almost a third of the tie with ten men, United can trouble this Bayern side.
4) Look To History... Sort Of
The Champions League has been going for 22 years, but no one has ever won it twice in a row. Which means that Bayern can't win it this season, and if they can't win it, then there is little point them trying to get beyond the quarter-final. History can't be wrong, can it?
Obviously I'm being slightly pr*ckish but, in fact, that's pretty much the reasoning that David Moyes is using to keep himself warm at night. Speaking after the draw was made, Moyes demonstrated some wonderful opti-logic:
"I've got a few things that I've seen that I would try to work on and capitalise on," Moyes stated.
Good to hear it David, that's kind of what we would expect. So, what's the plan. Target Toni Kroos (one booking away from suspension), high pressing on Philip Lahm or shoot low and from distance to try and catch out Manuel Neuer before he is fully set? Erm...well no.
"They are the holders. But I don't think the holders have ever won it twice. Hopefully we can try and do something about that. It's a really big game."
Those quotes were presented in The Guardian under a headline that read 'David Moyes: Manchester United can exploit Bayern Munich weaknesses'.
According to Moyes, Bayern's weakness appears to be just being very, very good. Thanks. For. That.
5) End Of The Road
It might not be a crumb of comfort for hopes of winning the Champions League, but if United are crushed by Bayern (and the odds of United winning at home on Tuesday are the same as Bayern to win by three goals), it would surely spell the end of the Moyes era/experiment/debacle/shambles.
Silver linings on clouds, anyone?
Daniel Storey - Follow him on Twitter.