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