Whether it be regular starters and star names such as Paul Pogba and David de Gea, or basement-level squad players such as Marcos Rojo and Phil Jones, virtually all of them have been linked with a move away from Old Trafford this summer.
There appears to be only one man at United who hasnt had his future queried so far but the player in question should be one of the first to be shown the door.
Nemanja Matic has just completed his second season for the Red Devils and yet his best performance for the club remains his first one for them in the Premier League.
An opening day 4-0 victory over West Ham United at the beginning of the 2017/18 season seemed to be a sign of great things to come, with then-manager Jose Mourinho starting what is usually his title-winning second season at a club with his two main summer signings, Matic and Romelu Lukaku, playing superbly.
While Lukaku somehow managed to keep up the facade that he might be good enough to play for United for a few weeks afterwards, for Matic that was as good as it got.
Since then, United fans have been subjected to two years of ever-decreasing levels of performance as the 30-year-olds body has given up on him.
To make matters worse, during that time his ability on the ball has also deteriorated.
And yet, while he is the epitome of everything thats wrong with the current United squad - slow, ponderous, poor on the ball, lethargic, only getting worse - he appears to be missing from the cull which is surely on its way during this transfer window.
Manager Ole Gunnar Solskjaer has made it clear what type of player he is after - young, energetic, progressive, potential to improve - and yet, despite Matic being the antithesis of that, it seems like the Norwegian wants to keep him.
To allow Ander Herrera, whose energy and passion have been vital in the last few dreadful years, to leave on a free and retain the Serbian international, whose lack of those qualities have been a key part of the reason for such abject displays in the last two campaigns, is an awful decision.
While nothing more can be done about Herrera now, another part of the problem can still be rectified by selling Matic this summer.
As a holding midfielder there are two main aspects to the job: the ability to snuff out danger and protect the defence when the opposition have the ball and how to use the ball when your team has possession.
In most cases, players are so excellent at one that they make up for being not quite so good at the other.
For example, the likes of Toni Kroos and Miralem Pjanic are better with the ball than without it and play the sitting role in midfield as a deep-lying playmaker, using their range of passing to help build attacks.
Others such as NGolo Kante and Fernandinho are better without the ball, using their defensive skills to win back possession and move it quickly to the more creative players in their side.
Unfortunately, Matic is not good at either.
His passing is poor and not nearly progressive enough. Too often the ball goes backwards and sideways when at the feet of the former Chelsea man instead of it being played forwards to find Uniteds attacking players.
How Nemanja Matic is programmed:1) Receive ball2) Look up3) Take 5 touches4) Pass sideways or backwards #MUFC
— Sam (@Sam__MUFC) November 27, 2018
Defensively he is no longer good enough as well.
Far too often since arriving in Manchester, Matic has been either overrun and overpowered by the opposition midfield or outsmarted by the more elusive attacking schemers at home and in Europe.
United are in desperate need of a major upgrade in such a crucial position.
A move for West Ham midfielder Declan Rice should be a no-brainer, with the 20-year-old having both the defensive and offensive skills required to be a huge success at Old Trafford.
The England international would be a huge improvement on Matic right now and that gap between the pair is only going to increase in the coming years as Rice develops and gains more experience.
Academy prospect James Garner should also make the step up to the first team next season as it is this type of player that Solskjaer should be focused on, not trying to get a bit of life out of a player who is way past his peak.
If the United boss truly wants to change the culture and style of football at the club then he must make sure Matic is one of the first to leave this summer.
However, it may take him a while to get to the exit door.