Currently sitting a lowly seventh in the Premier League and on the verge of going out of the Champions League to Olympiacos, after a 2-0 first-leg loss in the last 16, changes will need to be made in the summer.
And it seems that Moyes will be looking to make wholesale changes in an attempt to return the Red Devils to their former glory.
Moyes is understood to want up to eight new signings to revive the struggling Barclays Premier League champions after a disastrous season.
Rio Ferdinand will follow Nemanja Vidic and Anderson out of Old Trafford, and there are serious question marks over the futures of Patrice Evra, Robin van Persie, Shinji Kagawa, Nani and Javier Hernandez.
However, implementing such a large turnaround of players will be massively complicated by the demands of the World Cup, the increasing possibility that United could be involved in Europa League qualifiers, and the club’s pre-season tour of the USA.
Despite the problems that will face the 50-year-old as he tries to do business this summer, he really has no other option. This United side needs to be completely rebuilt.
One startling feature of United's play this year has been their weakness in defence.
With the old guard of Ferdinand, Vidic and Evra on the way out—and the obvious replacements of Chris Smalling and Phil Jones flattering to deceive—a complete rebuild at the back is a necessity.
As well as new centre-backs, Moyes should continue his attempts to bring in Leighton Baines, a proven star with bags of Premier League experience. Baines would be a leader as part of a new-look defence.
As if Moyes did not have enough problems with an ageing back line, the midfield is even more threadbare.
With only Michael Carrick to rely on as a defensive midfielder and players like Antonio Valencia not quite fulfilling potential on the flanks, the Scot needs several new players in the middle.
Toni Kroos, with whom United have been continually linked, would be a terrific start, but he would not solve all United's problems.
United need strength in depth in the middle of the park, as well as at least one more threat on the wing.
However, it may be more difficult than first thought to keep hold of the Dutchman van Persie. If they lose him things will need to be even more drastic in the summer.
As well as all of these weaknesses in the United squad it is essential, if Moyes is to succeed, for him to mould his own squad.
Sir Alex Ferguson left not only a weak squad at Old Trafford but a squad created by him and imbued with his philosophy.
Moyes is right to want to bring in his own players and start his own era at the head of this majestic club.