Black Cats winger Charis Marvrais spent the second half of last season in Germany.
David Moberg Karlsson, Charis Mavrias and Valentin Roberge are all potentially good signings.
The Greek international has headed to Fortuna Dusseldorf.
The Greek international has not had a chance at the Stadium of Light.
Plenty of fringe players will be hoping for a chance against Arsenal at the weekend.
Sunderland are looking at making some changes this month.
Lynden Gooch, Charis Mavrias and Thomas Robson must be wondering why they have not been given a chance.
Liam Bridcutt, Charis Mavrias and Jordi Gomez might get a phonecall.
The Black Cats will be letting Will Buckley, Liam Bridcutt, Charis Mavrias, Valentin Roberge and Emanuele Giaccherini go.
Sunderland are hoping to offload El-Hadji Ba, Charis Mavrias and Valentin Roberge this summer.