SALIBY: They drop a soccer ball on the grass and then measure the sound of its bounce. (SOUNDBITE OF BALL BOUNCING) SALIBY: It's all about determining if the ball meets tournament regulations.

Because space is limited, the sport emphasizes ball control ... and soccer is the playing environment. While soccer is played ...

Researchers are working to grow grass that will offer the same level playing field for athletes at the various soccer venues that will be used during the 2026 FIFA World Cup KUOW is Seattle’s ...