"He will leave United one day because he won't play for 50 years," said Scolari.
"If he goes to another club, whether in one year or two years, I don't know. He's my friend. I like him as a father likes his son. But his life is his life.
"When I arrived in Portugal, Ronaldo was a kid. A young boy of 17.
"At that time, he had a good character. He was starting as a very good professional, but at that time he was already thinking about his future.
"He's improved himself, very well, in the five or six years since. More in Manchester than with the national team.
"He lives in Manchester 11 months of the year and spends only one month a year with the national team.
"I've seen him improve. Next season, I can see him as a captain with Portugal. He's a very good man, helps the other players, a good attitude on and off the pitch.
"Ronaldo, has grown up, matured. Now, at this time of life, Ronaldo is mature and is better than one or two years ago.
"Now he is one of the three best players in the world. I said that two years ago, and I repeat it now. I never said he was the best, and I won't now.
"I have some players here who are fantastic, and I'd never say they are the best. He is one of three, one of five, one of 10."