"I am going to work hard to help the club get where it should get, which is to top the league and win titles," the 27-year-old Portuguese international told reporters after he passed a medical examination.

"I am going to play as I did in Portugal so that Atletico is the best," he added.

Under the deal Benfica will get 20 million euros (27.3 million US dollars) for the attacking midfielder, a record transfer for the Portuguese club, and will have an option to take two Atletico players.

Liverpool made a move for Simao in August 2005 but the deal broke down just as the explosive winger was set to fly to Anfield for a medical after the English side refused to meet Benfica's asking price for the player.

Atletico had to fight off opposition from rival Spanish side Valencia and French champions Lyon for Sabrosa who was part of the Portuguese side that reached the Euro 2004 final and last year's World Cup semi-finals.

Simao, the top scorer in the Portuguese league in 2003, arrived at Benfica in 2001 from Barcelona for a fee of around 13 million euros after two seasons with the Spanish side.

Atletico, who finished seventh in the Primera Liga last season, have now spent nearly 50 million euros on new signings.

They have signed Uruguay striker Diego Forlan from Spanish side Villarreal, Brazilian left wingback from Santos and midfielders Luis Garcia from Liverpool and Raul Garcia from Osasuna.