Kaka was officially presented as a Real Madrid player in front of tens of thousands of fans and a huge media contingent at the club's Bernabeu stadium on Tuesday evening.An estimated 50,000-strong crowd - almost three times the anticipated number - turned up to watch the ceremony as Kaka was unveiled as Madrid's latest addition by club president Florentino Perez and honorary president Alfredo di Stefano.Kaka has penned a six-year contract and has cost Madrid a reported #56million.The 27-year-old former AC Milan playmaker will wear the number eight at Madrid next season.There had been speculation that Kaka would be handed the number five shirt that Zinedine Zidane had once worn for Madrid, but the new arrival will instead take up the number eight shirt formerly worn by Fernando Gago.