Tosic reveals Man Utd stars knew Ronaldo was going
United have accepted an £80m offer from Real Madrid for the Portugal star, who has been the club's leading scorer for the past two seasons.
Ronaldo's desire to one day play for Madrid was no secret but it was the need for a new challenge that was behind the move, according to Tosic.
''He told us he had won all the awards and he wanted to try something else,'' the winger said. ''I don't know if he had already signed for Real Madrid.
''He is going to again be the best player in the world. Last season he scored 42 goals, this time 27. And they all said it's his worst season because it was not enough. In Madrid he will be the best again.''
Tosic, 22, joined United from Partizan Belgrade in January but has so far made only three first-term appearances.
Currently with Serbia Under-21s at the European Championships in Sweden, he is hoping he can help fill the void left by Ronaldo's impending departure.
''Cristiano was the best player in the team and so someone will come in to take his place. I hope I will get the chance,'' he added.