The 25-year-old defender, who has been out of Benfica coach Quique Flores' plans this season, has been given the green light to try to impress Blackburn boss Sam Allardyce during a trial.

Joao Gabriel, Benfica's communications director, told PA Sport: "The only thing missing now is an agreement between Blackburn and Zoro.

"Our club have nothing to oppose against his possible move to Blackburn. Our manager has consented Zoro to negotiate with them.

"Whether there is a deal or no, we will make it public at an appropriate moment. Between both clubs there is nothing wrong. It is up to the player and Blackburn to deal."

Zoro joined Benfica last summer on a four-year deal, and, like Bolton's new recruit Ariza Makukula, has not appeared in a single game since Spanish boss Flores took over last summer.

Meanwhile, Portuguese website Maisfutebol has suggested Benfica have refused a 4.5million euro offer for Frenchman Hassan Yedba from Premier League Stoke.

Yedba joined Benfica from French side Le Mans last summer on a free transfer and has currently made the most appearances for the Portuguese giants this season with 15.