Since Jose Mourinho has taken over, there has been significant progress in this regard, but much work is still to be done, and the Portuguese boss has repeatedly claimed that new signings are key in making this possible.
United have already secured the signing of Diogo Dalot from Porto and Fred from Shakhtar Donetsk, but Mourinho is by no means done.
A number of top players have been linked with a move to Old Trafford, which may well be finalised by the start of the new season.
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However, where there are arrivals, there are also departures. And several players are rumoured to have been disgruntled by their lack of playing time, and indeed lack of attacking potency among the United ranks.
The likes of Anthony Martial, Daley Blind, Matteo Darmian, and Marcos Rojo are some that come to mind and may well be released before the new season begins in August.
The 30-year-old has been a part of Mourinho’s plans at United, but has struggled to cement his place in the starting eleven like many others.
While a move to his native Spain may seem lucrative to Mata, it is highly unlikely that a deal could pull through considering Barca’s sheer talent in midfield, with the likes of Ivan Rakitic, Philippe Coutinho, and even Ousmane Dembele on the wings.
The report comes as a surprise because Mata has never been one to complain about lack of playing time or ever even hint at a move away from the club, and remains a popular figure among the United faithful.