The defending champs open their campaign against Holland.
"Another world cup victory is motivation enough. Our aim is to win it a second time for our country," said Casillas.
"We have been the best team in the world for the last four years and it is up to us to see if we can carry on being the best. If we show willing and keep our feet on the ground we can certainly win it again, although it isn't going to be easy."
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