Casillas & Buffon slam ball
"It's a bit like a beachball," the Spain captain was quoted as telling Spanish media on Sunday, the day after the friendly in Innsbruck, Austria. He went on to describe the unpredictable movement of the ball.
"Now it isn't only the goalkeepers (complaining) it is the outfield players as well. It's sad that a competition as important as a World Cup has an element as vital as the ball with such abysmal characteristics."
Midfield playmaker Xavi said: "It's a question of getting used to it but in truth it does move around a lot."
Italy goalkeeper Gianluigi Buffon joined the chorus of disapproval.
"The new model is absolutely inadequate and I believe it is shameful to play such an important competition, where so many champions are taking part, with a ball like that," the 2006 World Cup winner told his website.
The Adidas World Cup ball, whose name 'Jabulani' means 'to celebrate' in the Zulu language, was billed as the first perfectly round ball and the most accurate yet when it was unveiled by FIFA.
New balls for major tournaments always make players uneasy and there has been plenty of anger this time with the World Cup in South Africa due to kick off on June 11.
Brazil goalkeeper Julio Cesar has said the ball is "terrible, horrible" and like one purchased in a supermarket while Italy striker Giampaolo Pazzini said it was a "disaster" for both goalkeepers and forwards because it is so light.