Real Madrid hero Iker Casillas rates Juventus star Cristiano Ronaldo ahead of Barcelona ace Leo Messi.

Though the former goalkeeper accepts the talent that Messi possesses, he believes it is Ronaldo's work ethic that separates the great rivals.

"Cristiano always had huge desire to be the best, ever since he was a boy and I believe he has achieved that," the Spaniard told ESPN.

"If I have to compare him to Messi, what Cristiano has done is more impressive because we all know the talent Messi has, but Cristiano was determined and worked hard to be the best.

"I feel we have been lucky to have been able to enjoy two phenomenal players.

"For people that don't know Cristiano, he can appear to be cocky and arrogant, but it's totally the opposite."