Manchester United forward Bebe has signed for Benfica on a four-year deal for a fee of up to £2.4m (3m euros).
The 24-year-old told Benfica's official website: "I want to give many goals and lots of joy to the fans."
United will retain a 50% sell-on fee clause.
Bebe moved to Old Trafford in August 2010 from Portuguese club Vitoria de Guimaraes for a reported £7.4m - despite then-boss Sir Alex Ferguson having never seen him play.
He had only been at Vitoria for five weeks following a move from third tier side Estrala da Amadora.
The former Portugal Under-21 international made only seven appearances in four years for United, scoring two goals.
He made just two substitute appearances in the Premier League.
He joins Benfica on the back of the the Eagles completing a domestic treble - although they lost to Sevilla in the Europa League final.
Manchester United's official website released a statement, which said: "Everybody at United would like to wish Bebe the best of luck for the future."
Bebe spent last season on loan with Pacos de Ferreira, playing in the Primeira Liga, where he scored 13 goals in 32 games despite the club being relegated.
He was sent out on loan in 2011 to Turkey's Besiktas where he suffered a serious knee ligament injury.
Another loan move to Rio Ave in Portugal during the 2012-13 season was unsuccessful.