Valencia striker David Villa rates Real Madrid goalkeeper Iker Casillas as the best in the world.

Villa is working with Casillas this week as part of Vicente del Bosque's Spain squad.

He said: "Casillas is the strongest of all. I've seen few goalkeepers who can make saves like him. Right now I think he is also taking the place of Gigi Buffon (Juventus) and Julio Cesar (Inter Milan)."