Manchester City defender Ko Itakura wants to stay at Schalke after the expiry of his current loan in the summer.
Itakura, 25, has spent six months in Germany after a two-year loan spell at FC Groningen in the Netherlands. The Japan international was wanted by Celtic in the summer, but instead headed to Schalke for the season.
Schalke have a £5million option to make the move permanent, which could help boost City's summer transfer budget if the clause is triggered. If that happened, City would also have a 15 per cent sell-on clause on any future transfer.