The left-footed center-back has impressed with his pace and composure, making him a target for Europe's elite. Despite interest from the Red Devils, Werder Bremen is reportedly resigned to selling the German U21 international this summer.
To facilitate the transfer, Werder’s managing director Clemens Fritz has set a valuation between €40-50m (£34.8m-£43.5m). While Chelsea are already in talks with his representatives, United are keeping a close watch on the defensive prospect.