Patrice Evra is bidding farewell to Manchester United after 300 appearances for the club.
The French international's departure to Juventus follows the deal to bring England international Luke Shaw to Old Trafford from Southampton.
The exact fee for 33-year-old Evra hasn't been confirmed but Sky Sports says it is thought to be around £1.5m.
Evra said on United's official website he had given his decision to depart from Old Trafford "a great deal of thought" but felt that "the time is right for me to leave Manchester United".
"It is the biggest decision of my career as this club is, and always will remain, in my heart," he said.
"Joining and playing for Manchester United has been a privilege, a dream come true and my time here has been so memorable."
He also thanked Sir Alex Ferguson and the fans: "Every single time I stepped out in that shirt, I knew I was playing for the badge and for a very special club. My passion for this club will live on and I know you guys will go on to enjoy more success in the coming seasons."
News of his departure comes as the leadership at Manchester United sent strong signals of more additions ahead of the new season.
The club is looking to strengthen its squad in the hopes of a more noteworthy finish at the end of the forthcoming Premier League than last season's seventh place.
The suggestion of more players being brought in makes sense as the retirement of Ryan Giggs and the departure of Nemanja Vidic and Rio Ferdinand have created some space.
The club has already spent £56m bringing in defender Luke Shaw and midfielder Ander Herrera, but executive vice-chairman Ed Woodward told MUTV: "There is a lot of work going on behind the scenes. Watch this space."
