Werder Bremen have suffered a major blow after Salim Musah picked up a significant injury to his left thigh while representing Germanys U-20 side on international duty.The 20-year-old forward is expected to miss several months, leaving the Bundesliga club without a promising attacking option during a crucial part of the season.Werder coach Daniel Thioune admitted the diagnosis was particularly difficult for both the player and the squad. This is…