If we just bought tennis balls out of a bin or in an open box, they would lose this internal pressure. But because they come sealed, they are as pressurized as the day they were made, ready to bounce.

Tennis balls leave marks on all surfaces, but they are practically invisible to the naked eye on hard and grass courts, although on grass, chalk can sometimes fly up if a ball lands on or close to ...

Aryna Sabalenka’s ball-mark photo and the tennis dilemma of electronic line calling on clay By Charlie Eccleshare and Matthew Futterman April 21, 2025Updated April 23, 2025 21 ...

LONDON — Wimbledon is replacing line judges with electronic line-calling, the latest step into the modern age by the oldest Grand Slam tennis tournament. The All England Club announced that technology ...

The tournament has used line-calling technology to call whether serves are in or out. Here's what it looks like on the baselines at a Wimbledon this season without line judges: ...

For decades, tennis events played on clay have relied on human line judges calling the bounce of the ball and chair umpires coming down to inspect the marks they leave in the red dirt.