The wires in the ball are small and robust enough to survive the impact of being kicked around for 90 minutes, and they weigh so little that a GoalRef ball is indistinguishable from a regular one. "If you don't know that it's a special ball, you cannot decide whether it's normal or one with the special technology," says Rene Duenkler, a scientist with GoalRef. The ball is even approved by FIFA for use in games.
The distinction between these two technologies is that one is camera-based and one is not. And that difference could be the deciding factor. Unlike tennis, where there is almost never any thing or person obstructing the line of sight between the cameras and the ball, soccer presents unique challenges—especially during free kicks and corner kicks. In such situations, 10 players might be close to the goal, making it harder for cameras to unambiguously record when the ball passes the line. Hawkeye declined to comment on its technology, as it is still in the testing phase, but the company's Web site notes that it is dealing with a way to compensate for the problem by using multiple camera angles.
Not everyone is keen on goal line technology. Michel Platini, head of the Union of European Football Associations (EUFA), worried that introduction of this technology would begin a slippery slope toward more intrusions to the game, and he stood staunchly opposed to the technology. So even if UEFA is not on board, FIFA is, and the next international soccer stage will feature a new prop—a technology that will help enforce the line between winners and losers.