Fourth-ranked Paula Badosa of Spain broke serve twice late in the final set before winning a tiebreak to get past 21-year-old Elizabeth Mandlik 6-2, 5-7, 7-6 (5) at the Mubadala Silicon Valley Classic on Wednesday.
Other winners in San Jose were Wimbledon runner-up Ons Jabeur of Tunisia, No. 7 seed Daria Kasatkina of Russia and unseeded American Amanda Anisimova, who ousted eighth-seeded Karolina Pliskova of the Czech Republic 3-6, 7-5, 6-1.
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Jabeur, the No. 3 seed, defeated Madison Keys 7-5, 6-1 and Kasatkina defeated another American, Taylor Townsend.
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Mandlik, the daughter of four-time Grand Slam winner Hana Mandlikova, twice served for the match against Badosa while leading 5-4 and 6-5 in the decisive set.
But Badosa broke both times, then won three of the final four points of the tiebreak.
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The schedule for Thursday’s round of 16 in the hard-court U.S. Open tuneup includes four-time Grand Slam champion Naomi Osaka of Japan taking on American Coco Gauff.