Istanbul: Borussia Dortmund's Japanese international midfielder Shinji Kagawa on Thursday joined Besiktas on loan for the rest of the season, the Turkish club said.
The 29-year-old former Manchester United player had reportedly been a target of struggling French club Monaco.
Besiktas in a statement said Kagawa would be "a part of its team on loan until the end of the season".
Kagawa had earlier passed a medical examination after arriving in the city on Thursday to complete the deal.
Turkish media previously reported that the club had the option to buy the player but Besiktas made no reference to this in its short statement.
Kagawa helped Dortmund win the German league and cup double in 2012 before spending two years at United, then returned to the German club in 2014, but has fallen out of favour under coach Lucien Favre.
"We have a lot of understanding for Shinji's situation and for his wish to get more playing time at another club," said Dortmund's sports director, Michael Zorc.
"Shinji sees he has this possibility in Istanbul and we were happy to fulfill his wish."