West Ham have paid UNAM Pumas 4 million pounds for 23-year-old pacy winger Barrera, while Piquionne has moved for an undisclosed fee. Barrera, who played three times for his country at the World Cup in South Africa, has signed a four-year contract with manager Avram Grant's side.
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"I am very happy to sign for West Ham United and have been really taken by the reception I have received from the players and the manager," Barrera told the club website.
"I am very fast and can use both feet. I like the one-on-one situations and to take on my opponent and beat my rivals. I like to excite the supporters."
"I'm very happy to sign for West Ham because my last manager was Avram," the powerful striker told the club website.
"I know Avram and I like working with him and I think he likes me. I'm coming to work hard for the squad and I hope we have a good season," the ex-St Etienne forward added.
