The Latest: Williams drops 1st set of US Open quarterfinal

NEW YORK (AP) — The Latest on the U.S. Open tennis tournament (all times local):

1:05 p.m.

Serena Williams has dropped the first set of her U.S. Open quarterfinal against unseeded Tsvetana Pironkova by a 6-4 score.

Pironkova is playing in her first tournament in more than three years after taking time off to become a mother.

She broke Williams to lead 3-2, then failed to convert two set points while Williams served at 5-3.

But Pironkova served it out in the next game. She won 20 of the 25 points she served in that set.

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12:15 p.m.

Serena Williams is about to start her U.S. Open quarterfinal against unseeded Tsvetana Pironkova.

Williams is seeking her seventh championship at Flushing Meadows and record-tying 24th Grand Slam singles title overall.

Pironkova is a 32-year-old from Bulgaria who is playing in her first tournament since she took a break of more than three years while having a son.

The other women’s quarterfinal on Wednesday’s schedule is No. 16 seed Elise Mertens against unseeded Victoria Azarenka, who has a nine-match winning streak.

The men’s quarterfinals Wednesday are No. 2 seed Dominic Thiem against No. 21 Alex de Minaur and No. 3 Daniil Medvedev against No. 10 Andrey Rublev in an all-Russian matchup.

Medvedev was the runner-up in New York last year.

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