#3 No consistency in defence
Ole Gunnar Solskjaer chose to go with a three-man defence against Paris Saint-Germain with Axel Tuanzebe, Victor Lindelof and Luke Shaw holding the line at the back for the Red Devils. They were excellent and kept the extremely talented PSG attack at bay with some wonderful tackling and interceptions.
Alex Telles and Aaron Wan-Bissaka put in impressive shifts as the wing-backs too. Solskjaer subsequently decided to revert to a back four with Lindelof and Maguire as his centre-backs in the weekend game against Chelsea. There was no Telles in the squad.
Though Tuanzebe produced a mesmerizing performance against PSG, it was the first time he had played in about ten months and it's not something that should be expected of him every time he steps out without playing time and experience.
As such, it will be interesting to see what combination Solskjaer goes with at the back but do not be surprised if Manchester United defence look shaky against RB Leipzig.
#2 The pressure is on Manchester United
For a team that fantasizes too much about returning to their glory days, this should be bread and butter. However, the amount of media scrutiny on the manager and the players at Manchester United has grown to toxic levels.
The media has been trying to cook up a storm about Donny van de Beek's absence from the first-team. Marcus Rashford is told to go focus on his football. Media outlets are racing around trying to find replacements for Solskjaer.
To add to this, the Manchester United players did not have a proper season break to recover before the new season. They are just finding their fitness and a lot of players look set to hit their strides. Also, the win against PSG boosted the spirits of the players and the fans immensely. A loss against RB Leipzig could be deflating.
As such, there is a lot of pressure on Manchester United to win- to keep their run going, to turn their home record around, for Solskjaer to keep his job, for the players to prove their worth.
#1 RB Leipzig have been flying
Coming to the most obvious reason why Manchester United should be worried, RB Leipzig are the farthest thing from a pushover. They have been flying this season and are currently at the top of the Bundesliga table, ahead of Bayern Munich and Borussia Dortmund.
They are yet to taste defeat this season and have not looked like they miss Timo Werner much. They were fully in control against Istanbul Basaksehir and Julian Nagelsmann's side can give any team a run for their money on their day.
RB Leipzig have had seven different scorers and 16 players have already been directly involved in a goal (via goal or assist). That means that Leipzig have been attacking from everywhere and their players are in great shape.
Angelino and Yussuf Poulsen have been excellent so far for Leipzig and they are all set to torment a shaky Manchester United defence tonight.