Ronaldo, who made the switch to the Santiago Bernabeu from Manchester United in 2009, cost the Spanish giants a world record £80m transfer fee. This season, the Portugal international has scored 40 goals in 32 appearances for Los Blancos.
"Cristiano proves he is the best in the world in each match," he said. "We are all aware of how important he is to the team.
"The fight isn't between Ronaldo and Messi, but rather between two sides that want to win the title.
"Ronaldo has been at risk of seeing a fifth booking for two months and still hasn't. He is intelligent. There's no problem there."
Meanwhile, Los Blancos host Sporting Gijon in La Liga tonight.