Southampton have signed England under-21 international Jack Cork from Chelsea on a four-year deal.
The 23-year-old was on loan at the Saints during the 2008/09 season and has also had spells at Coventry, Watford and Burnley.
The Clarets, as well as Nottingham Forest and Blackpool, were thought to be keen on signing the midfielder.
He told the Saints' website: "I've been wanting to get away for a while and have been waiting for the right move."
Cork added: "The chance to come to Southampton came along, and having known the manager and having been here before and knowing some of the guys, it just felt like it was the right move for me."
Cork, who has been at Chelsea since he was nine and captained both the under-18s and reserves, has also represented England at every level from under-16 to under-21.