Reading have secured the services of Sporting Lisbon captain Daniel Carrico.
The 24-year-old, who can play in midfield as well as in defence, has signed a contract at the club until 2015, with the option of a further year.
Carrico, who would have been out of contract in June, moves to the Madejski Stadium in a 750,000 euros (around £600,000) deal which includes a sell-on clause for a future transfer.
In a farewell letter posted on Sporting's website, Carrico said: "It is with mixed emotions that I write this farewell message.
"I'm leaving the club of my heart, where I had the privilege of graduating (through the youth ranks) and serving for several years.
"I'm leaving because I understand that I am at a stage in my career when I have to take chances. Moreover, the proposed project is extremely exciting to me and know I can succeed."
A statement on Reading's official website read: "Reading football club are delighted to confirm we have agreed a deal to sign Sporting Lisbon's club captain, midfielder Daniel Carrico.
"The 24-year-old joins the Royals to begin the club's investment in this January window.
"He is a versatile player and can play in the centre of defence as well as in midfield. He has signed a contract until the summer of 2015, with the option of a further year."
Carrico, who will join up with his team-mates later this week, has featured just twice for Sporting this season as his future remained in doubt but arrives with Champions League and Europa League experience, having faced Barcelona and Manchester City respectively.
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