At this stage I don't think any target from Man Utd is overly realistic as I can see a change of manager there before the window opens, which could throw everything being speculated on up into the air. Lingard may be a possibility only due to his contract running out, however if they were to employ Zidane and he started getting some game time and a new contract offer, would he really turn that down? I don't think he would.
It doesn't pay as well to sign on to your current club as it does a new one - especially one taken over by the richest owners in the world...
Just from the EPL, 28 or younger out of contract in the summer:
----------Rudiger, Christiensen, Tarkowski,
Chambers, -----------------------------------Amartey,
-------------------Lingaard, Pogba, Cantwell,
---------------------------Origi, Nketiah,
Not saying we'd get all of them but there are some pretty interesting names there. The one I wouldn't want would probably be Pogba but lets face it we'd all be at "defcan 1" if he signed.
3/4 of those would transform our squad - any of the back 3 there, Cantwell, Amartey and Origi say...