Ralf Rangnick is already encountering an issue with one United player who was key under Ole Gunnar Solskjaer.
Aaron Wan-Bissaka saw his game time limited initially under Rangnick, but the £50million full-back has played the past two games and looked incredibly poor in possession.
United lost 1-0 to Wolverhampton Wanderers and in his post-match comments, Bruno Lage seemed to suggest that he deployed a mid-block and forced United's possession mainly to the right-hand side.
This was in order to give Wan-Bissaka the lion's share of United's chance creation, as they did not see him as a threat.
And they were right. The former Crystal Palace youngster's crossing was poor. Some sailed over Cristiano Ronaldo's head, others hit the first defender and some he miskicked and saw trickle out for goal kicks. This is not what you want to see from a right-back in the modern day.
Diogo Dalot has been an upgrade on Wan-Bissaka when he has played, but he still has his limitations and does not seem to thrive fully in the half-spaces
Neither are at the level of Luke Shaw on the opposite side, who becomes less useful if his opposite full-back is not effective as teams will move over to cover him more.
Manchester United will be envious when they see Trent Alexander-Arnold thriving in that role for Liverpool on a regular basis.
He has his problems defensively and sometimes it does seem like a numbers game that if he puts in enough crosses he will eventually create a chance, but having watched Wan-BIssaka fire in a high number of unsuccessful crosses, it seems that maybe it isn't just a numbers game.
Whenever Alexander-Arnold plays he creates goal-scoring opportunities for his forward line, as was the case when he put Mohammed Salah through to score Liverpool's second in Sunday's 2-2 draw at Chelsea.
When you're looking to dominate the game, an attacking full-back is more valuable than a defensive one. It seems that is the direction that Rangnick wants to go with United, so is there still a place for Wan-Bissaka?
Furthermore, if Erik ten Hag or Mauricio Pochettino arrive in the summer they will also want an attacking full-back, meaning that if Wan-Bissaka doesn't find a way to evolve his game and become useful in possession, his future at Old Trafford may be in danger.
If United want someone who can rival Alexander-Arnold or even Reece James at Chelsea they should look at Noussair Mazouri, who is currently impressing with Ajax and whose contract expires at the end of this season.
He would be the significant upgrade Rangnick needs at full-back and provide a creative balance with Shaw on the other flank.
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