The midfielder has nothing but praise for his "spectacular" Real Madrid team-mate and believes that the Portuguese deserves the Ballon d'Or for his impressive performances
The Portugal international is one of the leading candidates to win the prestigious individual trophy, alongside Franck Ribery and Lionel Messi.
Casemiro feels that it would only be logical if Ronaldo emerged victorious following his fine performances in 2013.
"He has to win the Ballon d'Or. He is spectacular," the Brazilian told the club's official website.
"There is no doubt that he is the best player around right now. If he scores two goals in a match, he always wants more and keeps on giving.
"I always watch what he does. He trains well, is always happy and has always helped me."
The midfielder also voiced his admiration for former Madrid greats such as Zinedine Zidane and Ronaldo.
"Zidane is the best player and a great person," Casemiro, who has made three appearances in La Liga so far this season, enthused. "Ronaldo Nazario is spectacular. It's a dream to be at the same club as these great players, I never imagined it."