#4 Marcos Rojo
Another one of Louis Van Gaal's recruitment, Marcos Rojo did arrive after a good World-cup with the Argentinian team but his United career has been simply plagued with injuries. If anyone has looked at him consistently, it is easy enough to make out that he does have the potential to become a strong centre-back option and he did prove it when he formed such crucial partnerships with Chris Smalling and Eric Bailly respectively during different phases but from last season, his injuries have become very common and it's gotten increasingly frustrating for some of the fans of the club.
He appeared in only 9 games last season and he's not appeared for even a single one this year. Manchester United remained in the hunt for a centre-back during the summer and it does look like they will definitely move for a centre-back next transfer window and at that time, it looks like a good option for Rojo to depart and focus on getting better else-where and then to cement his place. Interest from Everton and Wolverhampton Wanderers was clear during the summer and such options are great ones for Rojo to take. Only time will tell but he can surely opt to move and in my opinion, he definitely should.