Chelsea striker Demba Ba has completed his move to Besiktas, the Turkish club has announced on its website.
Besiktas claim the deal for the 29-year-old Senegal striker is worth six million Euros (£4.7m).
Ba passed a medical on Friday after posting a picture of himself wearing a Besiktas shirt.
"I've had a lot of positive feedback about Besiktas and Istanbul from my Senegalese friends in Turkey," he said on the Beskitas website.
"To play in a Muslim country and in a new stadium is definitely very exciting.
"I know what my coach Slaven Bilic expects from me, and I am open to all sorts of competition.
"Since Besiktas fans like hard-working and spirited players, I will give everything I've got in order not to disappoint them."
The transfer has been declared with the stock exchange in Turkey.
|Turkish delight for Ba|
|Besiktas, who are managed by former West Ham and Everton defender Slaven Bilic, are 13-time Turkish champions.|
|Last season they finished third in Super Lig, behind Istanbul rivals Fenerbahce and Galatasaray.|
Ba is likely to join Besiktas at their pre-season training camp in England.
The former Newcastle forward only started 23 of his 51 appearances for the Blues, scoring 14 goals, as he found himself third choice behind Samuel Eto'o and Fernando Torres.
"Ba is a player we all believe in, we put in a lot of time and effort to complete the transfer," said Besiktas president Fikret Orman. "The transfer is within our budget and we are delighted to have completed the move."
Ba joined the Blues from Premier League rivals Newcastle in January 2013 on a three-and-a-half year deal for an undisclosed fee.
It was thought his contract with Newcastle allowed him to speak to other teams if the club received a £7m bid.
He scored 29 goals in 57 appearances for the Magpies after joining on a free transfer from West Ham United in June 2011.