#4 Luka Modric
As stated earlier, defence is Mourinho's major problem, but their midfield too, is not much different from that. Despite having many star midfielders, they have not really been able to command every game they play.
Many of their players, whom Mourinho thought would command their ship, have been failing to impress the Portuguese. Apparently, he's impressed with Modric's performances, who has been doing great in the Real Madrid midfield.
According to Marca, Real Madrid have given priority to replace this ageing midfielder with a more young, talented one. Bringing him in would help Mourinho finally find a creative player to partner Paul Pogba, who has been below-par.
With Mourinho in dire need of a midfielder to control the game from the middle of the park, it seems like Modric could be on his way to the Old Trafford.