Around 35,000 Barcelona fans went to the Nou Camp to see striker David Villa presented on Friday as the club's first signing since they won a second consecutive La Liga title last weekend.
He had a buy-out clause of 200 million euros, Barca said on their website (www.fcbarcelona.com).
Villa will be leading the line for Spain at the World Cup finals next month, along with new Barca team mates Xavi, Andres Iniesta, Gerard Pique, Carles Puyol, Pedro, Sergio Busquets and Victor Valdes.
"One of the many reasons that helped me make my decision to go to Barca, once Valencia said they wanted to sell me, was the friendship I have with many of them (the players)," Villa said.
"I know I won't have any problems because many of them have already helped me to become a Barcelona player."
The quietly-spoken Asturian added: "I am proud that Barca returned to try and sign me (after an unsuccessful attempt last season). I have always been clear about where I wanted to go."
Barca's sports director Txiki Begiristain said Villa's arrival did not threaten Swedish forward Zlatan Ibrahimovic's future at the club.
"David is an extraordinary number nine but can also play out wide, he is completely compatible with Ibrahimovic," Begiristain said.
"The season is very long, and we need forwards of great quality, and now we have covered every type of profile. There isn't a perfect XI and coach Pep Guardiola will decide in each game."
With World Player of the Year Lionel Messi a definite up front and youngsters Pedro and Bojan Krkic pushing for places the player most likely to be moving on is France striker Thierry Henry.
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