Spain coach Vicente del Bosque has expressed his confusion at Jose Mourinho's treatment of Iker Casillas at Real Madrid.

The Portuguese boss, who returned to take charge of Chelsea on Monday, played the Spanish goalkeeper just 19 times last season after falling out with him.

However, Del Bosque admits that he is bemused by the relationship as he feels that the shot-stopper has done nothing wrong.

"I find it hard to believe that Iker dropped out of the squad," said Del Bosque.

"It's hard to believe because I've known him for many years and his career has always been impeccable.

"I have not had the chance to speak to him since the game we played in France, but while it's none of my business and an internal matter for the club, I have no reason to believe it is true."

Casillas has been included in Spain's squad for the upcoming Confederations Cup.