#2 Toby Alderweireld
This is a player that the Red Devils have been linked with for a couple of years now as it becomes clearer and clearer that Toby Alderweireld will leave Tottenham in search of a better contract this summer.
As with the aforementioned Varane, the signing of the Belgian would massively stabilise a defence which seemed all over the place on occasion over the past year or two. Also, his price tag is reportedly very similar to that of Varane: just over £50 million. He has experience of playing in the Premier League and seems open to a move so all the signs are pointing in the right direction. As well as the fact that he is a marked improvement on Jones and Smalling, the players he would be replacing should he sign.
How the central defender performs during the upcoming World Cup will be a big factor in any potential offers from Ed Woodward but the 29-year-old's good track record would show that he is more than capable of performing to a top standard in a back four that is largely failing in its current state.