Castillo moved to Red Star in 2006 from El Nacional
Everton have completed the signing of Ecuadorian midfielder Segundo Castillo from Red Star Belgrade.
Castillo, 26, has joined on a season-long loan and Everton are hoping to get international clearance to allow him to play on Saturday against Portsmouth.
Castillo has made 33 appearances for Ecuador and is Everton's second summer signing following the arrival of Danish defender Christian Jacobsen.
"I hope I can do my best for the team," said Castillo.
"I know that Everton are a big club who have a history of playing in important competitions like the Uefa Cup."
Everton manager David Moyes has also been linked with gifted Nigerian striker Victor Obinna, who has just signed for Inter Milan but may be loaned out to gain experience.
Moyes and chairman Bill Kenwright have also not given up hope of luring Sporting Lisbon's Joao Moutinho to Goodison Park, although the Portuguese side are holding out for what would be a club record £18m fee.
Castillo had been on trial at Blackburn Rovers, but they could not agree terms with Red Star.
Primarily a defensive midfielder, Castillo played in three out of Ecuador's four 2006 World Cup games, including the 1-0 defeat to England.
Before moving to the Serbian side in 2006, he played for Ecuadorian club El Nacional after starting his career with El Deportivo ESPOLI.
The departure of Lee Carsley at the beginning of the summer left a midfield hole for Moyes to fill this season and the news of Castillo's signing will please Everton fans, especially after Juventus midfielder Tiago rejected a loan move last week.
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