Barca land gifted winger...
Mata, 22, has reportedly penned a five-year contract with Barca after the two clubs concurred on a €20 million fee for his services.
He has long been linked with a move to Camp Nou as Barcelona look to strengthen the left side of their attack, with Thierry Henry's future at the club still in doubt.
Valencia rejected Barcelona's approaches for Mata last summer, but with their financial problems meeting no improvement, they have been forced to part with another of their stars following the €40m sale of David Villa in May.
Mata, who had a contract with Valencia until 2012, will now become Barcelona's ninth player to wear Spain's shirt at the World Cup.
He also had the chance to move to Manchester City, but rejected the Premier League side's big-money offer as he planned to stay in his homeland.
It is believed the arrival of Mata at Barcelona will pave the way for the exit of Zlatan Ibrahimovic, who signed for the club last summer in a €69m move.
Can Spain lift the trophy? Check out Castrol Football's 2010 FIFA World Cup Success Predictor.
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