The Uruguayan, who announced his retirement this summer, spent one season with Ronaldo as his team-mate at Old Trafford in 2003/04.
The Portugal international, who went on to win three Premier League titles and the Champions League with the Red Devils, took David Beckham’s No.7 shirt after his move to Real Madrid.
But Forlan wasn’t impressed with Ronaldo’s off-field behaviour.
“Ronaldo was an egotist in the dressing room – not like Beckham,” he told Fox Sports, as reported by the Daily Star.
“Cristiano always wanted to be near a mirror. He spent all day looking in the mirror.
“Ronaldo was changing in front of the mirror, tremendous.
"Beckham was more natural, they are different. Beckham was dishevelled and fit, the other you never saw dishevelled."
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