Top-seeded Alexander Zverev got a warning from the umpire for taking a photo of a ball mark during the clay-court Madrid Open ...

Alex Zverev was given a warning for unsportsmanlike conduct after using his phone to take a photo of a disputed ball mark in ...

Sabalenka disagreed with a ball mark on the Stuttgart clay, a situation that electronic line calling would make even more ...

Tennis balls are made up of a hollow rubber core and a wool or nylon shell known as the nap. In tournaments they must be white or yellow in colour. The rubber core is usually filled with pressurised ...