United are keen to bolster their squad in the summer, with Ole Gunnar Solskjaer odds-on to be named as permanent manager.
The Norwegian has turned the fortunes of the club around and Ed Woodward is likely to bankroll a mega summer to back him up.
But a major issue at the Red Devils this season has been retaining the talent that they already have.
United have been locked in contract talks with a number of important players this season, with differing results in success so far.
Anthony Martial, Phil Jones and Ashley Young have all signed new deals, while youngster James Garner has also put pen to paper regarding his future.
But they are also running into problems with several key players, including Ander Herrera and Marcus Rashford.
However, the most pressing issue is that of De Gea – with the fears growing that he could be on his way out.
United have been locked in talks with the Spaniard since the beginning of the season but little progress has been made.
It led to the club triggering a clause in his contract that extended his deal by a year – meaning it will now expire next summer rather than this summer.
The Red Devils were prepared to pay De Gea £300,000-a-week – making him the highest-paid goalkeeper in the world.
But that is not enough, with the Telegraph reporting that the 27-year-old demanding pay parity with Sanchez – who is earning around £500,000-a-week.
The Chilean has posed a number of problems for the Old Trafford outfit – on and off the pitch, with his performances below-par to put it mildly.
But his wages have caused raptures in the dressing room, with several stars demanding more wages.
De Gea is the most high-profile, but as of yet United are reluctant to bow down to his contract demands.
The former Atletico Madrid stopper will not short of suitors should his situation deteriorate further.
Paris St-Germain would snap up the star as the successor for Gianluigi Buffon while Juventus have also expressed an interest, looking to the long-term replacement to the same man.