Jose Mourinho stated after this weekend's 2-2 Clasico draw that people shouldn't compare the two as they're both from another planet, but Casillas has insisted that he prefers the Portugal star over the Argentine forward.
"I'd choose Cristiano over Messi because he's a player who gives us so much every season and he's a player I spend time with every day," Casillas told Cadena Cope.
"I know him, know who he is, know how he trains, know what he wants and where he wants to get to."
The shot-stopper also had his say on the difficult relationship between Sergio Ramos and Jose Mourinho, but refused to side with either of the two parties.
|RISING FROM THE DEAD|
|3/1||Real Madrid are 3/1 with bet365 to win La Liga this season|
"It's not a question of siding with Sergio or the boss but supporting everyone equally."
Ramos was benched for the Champions League win over Manchester City, but has since returned to the Madrid starting XI again.