New World Cup ball may be unpredictable

HERZOGENAURACH, Germany, June 9 (UPI) -- The new ball to be used for the first time in the World Cup's opening game Friday in Germany is likely to confuse goalkeepers, a scientist warns.

The Adidas "Teamgeist" ball has just 14 panels, with fewer seams, making its surface "smoother" than conventional balls, which have a 26 or 32 panel hexagon-based pattern.

This makes it aerodynamically closer to a baseball, said Dr Ken Bray, a sports scientist at England's University of Bath. When hit with a slow spin, the ball will be less stable, giving it a more unpredictable trajectory in flight.

"With a very low spin rate, which occasionally happens in football, the panel pattern can have a big influence on the trajectory of the ball and make it more unpredictable for a goalkeeper," Bray said.

The ball has been used in practice sessions by teams competing in the World Cup, and has already been criticized by England goalkeeper Paul Robinson and Germany's goalkeeper Jens Lehmann for its light-weight and unpredictable behavior.

Bray is also the author of the new science book, "How to score -- science and the beautiful game."