Chelsea have signed Portugal midfielder Deco from Spanish giants Barcelona on a two-year deal for a fee of about £8m.
The 30-year-old was recently told by Barca's new coach Pep Guardiola that he did not feature in their future plans.
"It is good for me to be here and first of all I am very happy to be here," Deco told Chelsea's official website.
Deco becomes the Blues' first signing since Portugal coach Luiz Felipe Scolari was appointed manager earlier this month.
However, his signing is Chelsea's second of the summer after international team-mate Jose Bosingwa.
Brazil-born Deco joined Barcelona from Porto in 2004 after helping the Portuguese side win the Uefa Cup, Champions League and domestic league titles under former Chelsea boss Jose Mourinho.
He won two league championships with the Catalan giants, and was part of the team that beat Arsenal in the Champions League final in Paris in 2006.
However, a series of injuries hampered him during the 2007-08 season, and he made just 14 starts in Barcelona's La Liga campaign.
Deco's arrival significantly boosts a midfield line-up already featuring the likes of Frank Lampard, Michael Ballack, Michael Essien, Jon Mikel Obi and Claude Makelele.
