Manchester United should forget about qualifying for the last 16 of the Uefa Champions League and focus on their Premier League matches because they have a big test to beat Bayern Munich on match day 6, which will be difficult for them to achieve. Onana will be another reason why Manchester United can not defeat Bayern Munich because of his errors.
It will be difficult to win Bayern Munich but it's aswell not impossible to win Bayern Munich so we can't be too sure till the game is actually over. It's true that on paper Bayern is the favourite and has got more edge then the red devils but then I think there's still a way out.
If Bayern Munich decides to try out their rotational squad because the outcome of this game has got no effect on them a they have successfully secured their spot at the round of sixteen already, in a case such as this were Bayern Munich decides to try out something in this light, Manchester united may get a chance at it because they may most likely have an edge a they will be playing at old Trafford so all this could possibly create a chance for Manchester united.
It seems to me that Manchester United cannot afford to give up on the UCL as their chances to make it to the next round are not as bad as it may seem, Bayern has already qualified and it makes not much difference for them if they win the match or not, so I think it is a given Bayern will give the chance to some of the players on their bench to see the field, and this could give Manchester United enough of an edge to get the win, and if Copenhagen and Galatasaray tie on their match then Manchester United will make it to the next round.