Arsenal will sell Shkodran Mustafi this summer if a team pays £22.3m for the Germany defender.
Signed two years ago from Valencia for £35m, Mustafi has largely frustrated under Arsene Wenger and Unai Emery, having run the rule over the Germany international, has decided he is surplus to requirements.
Galatasaray SK made an initial loan move, report Fanatik, but the Gunners want a permanent deal.
The signing of Sokratis Papastaphopoulos and a will to develop the likes of Rob Holding, Calum Chambers and Konstantinos Mavropanos means Mustafi is not needed at the Emirates.
A significant loss will be accepted, but that cut-price fee may not attract any suitors.