Zarina Diyas routed Germany's Fed Cup player and former Wimbledon runner-up Sabine Lisicki 6-0, 6-0 in the first round of the Porsche Grand Prix on Wednesday.

Kazakhstan's top player had lost in the first round of her previous two tournaments, but brushed aside Lisicki in 64 minutes on the indoor clay in Stuttgart. Diyas is ranked No. 32, while Lisicki is No. 19.

Seventh-seeded Agnieszka Radwanska of Poland also went out, losing 7-6 (8), 6-4 to Sara Errani of Italy. Radwanska had won seven of the previous nine matches against Errani.

Germany's Angelique Kerber beat Alexa Glatch of the United States 6-2, 7-5 and advanced to a second-round match with defending champion and top-seeded Maria Sharapova of Russia. Sharapova had a first-round bye.