# Tennis: Alexander Zverev is convinced there was a defect in the electronic line calling system during his Madrid Open win on Sunday. The German risked a hefty fine by pulling out his phone to take a photograph of a contested call. The top was frustrated when the tracking technology called in a backhand from his opponent. Zverev said he is a fan of the technology he was shocked by the incident in Madrid. The ATP from this year has adopted the line calling system for all its tournaments.
Tennis: Electronic line calls in question again as Zverev takes photo of ball mark