Injured Williams out of Madrid Open

Venus Williams has pulled out of the Mutua Madrid Open due to a back problem.

Organisers confirmed this morning that the world number 21, whose sister Serena is the defending champion and top seed in Madrid, had withdrawn from the tournament ahead of her opening-round match with Anabel Medina.

The seven-time Grand Slam winner, 32, was replaced by Stefanie Voegele and the Swiss suffered a 6-3 6-3 defeat to Spaniard Medina.

Williams said on the tournament's official Twitter page: "I was looking forward to playing, but unfortunately my back is hurting and I am not able to compete."