Petkovic withdraws from Tennis Grand Prix


World number 11 Andrea Petkovic has withdrawn from the Tennis Grand Prix in Stuttgart, which got under way on Monday.

Petkovic competed for Germany in their 3-2 Fed Cup defeat to Russia at the weekend but has withdrawn from this week's WTA Premier event with an apparent thigh problem.

"Really sorry to announce that I have withdrawn from the Porsche Tennis Grand Prix in Stuttgart," she wrote on Twitter.

"It is one of my favourite tournements [sic] and and also one of the few left in my home country.

"Have no words to express my disappointment and sadness but after all it is a decision I had to make in order to avoid any further risk for my health."

The first-round action did get underway on Monday, though, with wildcard Carina Wiffhoft surprising her German compatriot Mona Barthel - ranked 35 spots above Wiffhoft - 7-5 6-3.