Sports

Brengle upsets Kvitova at Porsche Grand Prix, Wozniacki advances to quarterfinals

  • Caroline Wozniacki of Denmark returns the ball to Lucie Safarova of the Czech Republic at the Porsche Grand Prix tennis tournament in Stuttgart, Germany, Thursday, April 23, 2015. (Marijan Murat/dpa via AP)

    Caroline Wozniacki of Denmark returns the ball to Lucie Safarova of the Czech Republic at the Porsche Grand Prix tennis tournament in Stuttgart, Germany, Thursday, April 23, 2015. (Marijan Murat/dpa via AP)  (The Associated Press)

  • Petra Kvitova of the Czech Republic returns the ball to Madison Brengle of the US at the Porsche Grand Prix tennis tournament in Stuttgart, Germany, Thursday, April 23, 2015. (Marijan Murat/dpa via AP)

    Petra Kvitova of the Czech Republic returns the ball to Madison Brengle of the US at the Porsche Grand Prix tennis tournament in Stuttgart, Germany, Thursday, April 23, 2015. (Marijan Murat/dpa via AP)  (The Associated Press)

  • Madison Brengle of the USA returns the ball to Petra Kvitova of the Czech Republic at the Porsche Grand Prix tennis tournament in Stuttgart, Germany, Thursday, April 23, 2015. (Marijan Murat/dpa via AP)

    Madison Brengle of the USA returns the ball to Petra Kvitova of the Czech Republic at the Porsche Grand Prix tennis tournament in Stuttgart, Germany, Thursday, April 23, 2015. (Marijan Murat/dpa via AP)  (The Associated Press)

Madison Brengle of the United States upset third-seeded Petra Kvitova 6-3, 7-6 (2) in the second round of the Porsche Grand Prix on Thursday.

Fourth-seeded Caroline Wozniacki won 7-6 (5), 6-1 against Lucie Safarova of the Czech Republic to reach the quarterfinals as well.

Brengle served for the match at 5-4 but Kvitova saved three match points to force a tiebreaker. Brengle took a commanding lead and won her first match over a top-10 player with a backhand passing shot.

Also, Caroline Garcia of France, Ekaterina Makarova of Russian, and Sara Errani of Italy advanced.