The 49-year-old thinks that Ronaldo's aerial ability and ambidexterity puts the forward above Messi as the overall best.
"Cristiano, taking into account all surfaces, is the best in the world," the former midfielder explained, according to Goal.com.
"He is better than Messi both with his feet and with his head. He is the more complete in the end - he has more resources because [he is good in] the air and hits the ball well with both feet.
"Messi has more trouble finishing with his right foot and because of his stature does not dominate in the air.
"It is difficult to find a better header of the ball than Cristiano. To me they are the two best players in the world."
The Spaniard's team sit one place behind Ronaldo's Madrid in the table, with the two sides facing off this weekend.