Euro 2012: All eyes on the Tango ball
As Euro 2012 begins, it is not only the players whose performance will be analysed, in previous tournaments the ball itself has become a point of discussion.
The official football is named "Tango'' and follows hot on the heels of the much-maligned "Jabulani" used at the 2010 World Cup.
BBC Sport's Tim Hague has been finding out just how important the design of a ball is.
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