Chelsea have ended a long-running saga by signing England defender Ashley Cole from Arsenal in exchange for £5m and defender William Gallas.
The deal was completed just before the transfer deadline with Cole, who was with the England squad in a Manchester hotel, having his medical nearby.
Cole is believed to have signed a five-year deal worth £90,000 per week.
Chelsea had been linked with Cole, 25, all summer, but disagreements over the transfer fee stalled the move.
A joint statement from the clubs said: "Chelsea FC and Arsenal have agreed terms for the transfers of Ashley Cole and William Gallas.
"Chelsea will also pay Arsenal £5m. Both players have agreed personal terms and passed their respective medicals."
Although all the relevant paperwork had been lodged with the Premier League, neither club had made an announcement by the time the midnight deadline passed. It was not until 0125 BST on Friday that the statement was finally issued.