Jose Mourinho spent £160 million in the summer transfer window, however, is still discontent with some areas of his squad.
Left-back has been a problem position for the Portuguese who is proving not to be a big fan of Luke Shaw.
The 54-year-old has instead opted for natural winger, Ashley Young, to deputise for Shaw at times - who has been struck by injury problems during his time at Old Trafford.
While that has been an issue, the man in question's biggest concern will have been his lack of game time this season - featuring for just 328 minutes in the Premier League this campaign.
And things could only get worse as rumours continue to grow surrounding a potential replacement for the 22-year-old former Southampton left-back.
Tottenham are understood to be interested in taking Shaw, who cost United £30 million to sign from the Saints back in 2014.
United and Spurs pursue youthful left-back
But they, too, could reignite their interest in another left-back target Mauricio Pochettino is chasing in the event that Danny Rose leaves next summer.
Rose and the Spurs boss' relationship was in question earlier this year and the Argentine has already lined a player who would fit the bill in north London.
However, according to The Guardian, United are expected to strongly contest Tottenham's interest in Fulham left-back Ryan Sessegnon and are preparing a £25 million bid for the 17-year-old Championship star.
The teenager has been earning rave reviews in England's second tier and Mourinho is willing to take the risk on the England youth international who is rated at £30 million by Fulham.
Fulham boss refuses to rule out sale
“In this moment, I am not thinking of being without him for the season, but it is not under my control,” Fulham boss Slavisa Jokanovic said, per The Guardian.
“All the questions are what the value of this player is, but myself, as a coach, I prefer to stay with the more important players for the competition that is ahead of us, but on the other side I can understand the business side too. If we want to be competitive we must keep our important players.”
Real Madrid's interest in the Championship star will no doubt have the west London club making it awkward for United to strike an easy deal they believe is a fair reflection of his value.
And that has been indicated by the £20 million plus add-ons bid Tottenham saw rejected in the summer, while Los Blancos scouts have since flocked to Craven Cottage.
Do YOU want to write for GiveMeSport? Get started today by signing-up and submitting an article HERE: https://www.givemesport.com/writeforgms