Cristiano Ronaldo's £80 million move to Real Madrid from Manchester United has been completed, the Barclays Premier League champions have confirmed.

The world-record transfer fee was agreed between the clubs for the Portugal winger last month and ends a three-year tug-of-war between the clubs for the player, which often descended into acrimony as United battled to keep hold of him despite his obvious interest in moving to Spain.

Sir Alex Ferguson said last year that he would not sell Madrid "a virus" but the United manager paid a glowing tribute to his former player today.

"Cristiano has been a marvellous player for Manchester United," Ferguson said. "His six years at Old Trafford have seen him develop into the best footballer in the world.

"His contribution has been a major factor in the club's success in that time and his talent, his ability to entertain and his infectious personality have enthralled fans the world over. Everyone here wishes him well in his future career."

The move makes Ronaldo one of the world’s best-paid athletes, with a £107 million contract over six years. He is expected to earn £9.5 million in the first year, rising 25 per cent a year to £29 million - a weekly wage of £557,000.

United have made a net profit of £68 million on the player they signed from Sporting Lisbon for £12.4 million in 2003. The 24-year-old was United's top scorer last season, with 26 goals. He is the reigning Fifa World Player of the Year and joins another costly new signing, Kaka, at the Bernabeu. The Portuguese is expected to be formally unveiled by the Spanish club next week.

United have already spent around £16 million on a new winger, Luis Antonio Valencia, from Wigan Athletic, but their interest in Franck Ribery, of Bayern Munich, seems unlikely to come to fruition.