Arsenal defender Shkodran Mustafi has completed his move to Schalke after terminating his contract at the Emirates.
The German international returns to his homeland as a replacement for Ozan Kabak, who sealed a move to £1.5m loan move to Liverpool late on deadline day.
Mustafi, who joined Arsenal from Valencia in 2016 for £35million, had fallen out of favour under Mikel Arteta and had only featured nine times in all competitions.
Schalke have given the 28-year-old a contract until the summer.
Mustafi made 151 appearances for the Gunners, scoring nine goals in his five years at the club.