After leading Madrid to the Liga title and La Roja to European Championship glory, many players and pundits have argued that Casillas deserves to be recognised with the most prestigious individual honour in the game.
And Zoff would enjoy seeing the 31-year-old shot-stopper land the award, but even as a fellow member of the goalkeepers' union, he finds it difficult to look past Barcelona attacker Messi, who has won the award for the past three years.
"I would be happy to give it to Casillas," the Italy legend told AS. "But, honestly, I cannot see it. I think Messi will win it again. For me he's the best player in the world; he is an artist.
"He is the best and Cristiano [Ronaldo] is very close to him. They are the two best players in the world. After that comes the rest: Casillas, [Andrea] Pirlo, [Gianluigi] Buffon."
Indeed, Zoff feels that just making the podium would be a fine achievement for Casillas, given the quality of his rivals.
"Anything is possible," the former Juventus man mused. "I got second in 1973 behind Johan Cruyff.
"But I think that a great result for Casillas would be second behind Messi. I think it's different for a goalkeeper. I think it's a prize for artists of the ball.
"Casillas has many attributes. He is so complete. There is no doubt that he is one of the greats. He's one the best goalkeepers in the world, along with Buffon and [Petr] Cech.
"But Messi is something else."
Zoff earned 112 caps for his country and remains the oldest player to have lifted the World Cup, having led the Azzurri to the title in 1982.