World No. 2 Alexander Zverev became the latest tennis player to question electronic line calling ... with umpire Mohamed Lahyani to inspect the mark. “The machine is not working.

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

but Schuurs and Muhammad referred to the ball mark and gave Azarenka a first serve. This kind of sporting behavior is acclaimed across tennis, but in this instance it has wider philosophical ...