NEW YORK (AP) Wimbledon champion Petra Kvitova is out in the third round of the U.S. Open.

The No. 3-seeded Czech committed 34 unforced errors in a 6-4, 6-4, loss Saturday to Aleksandra Krunic, a Serbian qualifier ranked No. 145.

Kvitova, who had a shot at the No. 1 ranking with a U.S. Open title and an early Serena Williams exit, becomes the fifth of the top eight women seeds to fall. She joins No. 2-seeded Simona Halep and No. 6 Angelique Kerber, who lost Friday, and earlier losers No. 4 Agnieszka Radwanska and No. 8 Ana Ivanovic.

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