Midfielder Mesut Ozil (33) has left Fenerbahce after his contract was terminated by mutual consent and joined Turkish top flight rivals Istanbul Basaksehir on Thursday.
The 33-year-old former Real Madrid and Arsenal player signed a one-year deal at Basaksehir with the option of a further year, the club said.
Basaksehir finished fourth last season, eight points behind second-placed Fenerbahce.
Ozil hadn't played for the club since March following a row with then-interim boss Ismail Kartal. The former Germany international only played 37 times across his season-and-a-half in Turkey.
Ozil still had two years to run on his contract.