Ronaldo is now in his third season with Juventus after being sold by Florentino.
Calderon said on Alarabi aljadeed, "He made a big mistake with Cristiano Ronaldo. Perhaps I am partial in this matter because Cristiano signed for me, but one of Pérez's main mistakes is that he did not accept the advice he received.
"In this matter he was constantly making comments about Cristiano and the relationship between them was not good. In the end he decided to sell and now he is offering a great level with Juventus, confirming that he is still one of the best players in the world and that he can play for three or four years easily."