Ashlyn Krueger of the United States returns a shot against Marie Bouzkova (not in photograph) of the Czech Republic during their Women's Singles First Round match on Day Two of the 2023 US Open at the USTA Billie Jean King National Tennis Center on Aug 29, 2023 in the Flushing neighborhood of the Queens borough of New York City. (PHOTO / AFP)

American teen Ashlyn Krueger didn't lose a set the entire tournament in capturing her first WTA Tour title with a 6-3, 7-6 (6) upset of top seed Zhu Lin on Sunday at the Japan Open in Osaka.

Ranked No. 123 in the world, Krueger, 19, entered the week without a main-draw win on hard court this year and had never advanced past a quarterfinal of a WTA event.

China's Zhu, ranked No. 35, became just the second top-50 player to lose to the Dallas resident in her young career. This was the pair's first meeting and Krueger's 11th main-draw appearance.

Krueger had the edge in aces, 7-3, and never had to save a break point in the 96-minute match. She broke Zhu on her first service game of the match, and Zhu was 1-for-2 in saving break points.

At the Guadalajara Open in Mexico, twelfth-seeded Anhelina Kalinina of Ukraine faced the least resistance among that group of winners, losing only two games in beating Grace Min of the United States 6-2, 6-0 in 61 minutes

"I think I was very aggressive today, playing a lot of really aggressive tennis and using my serve," said Krueger, who recorded 28 winners to 13 for her opponent. "I think I just stayed mentally tough the whole time. Lots of aggressive shots and trusting in myself."

Guadalajara Open

All four seeded players who were in action posted first-round victories in Mexico.

Twelfth-seeded Anhelina Kalinina of Ukraine faced the least resistance among that group of winners, losing only two games in beating Grace Min of the United States 6-2, 6-0 in 61 minutes.

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In a matchup of Belgians, 13th-seeded Elise Mertens survived a first-set tiebreaker to defeat Yanina Wickmayer 7-6 (4), 6-2. Mertens had eight aces and won 25 of 35 first-service points.

No. 15 Jasmine Paolini of Italy had a harder time in the second set than the first, defeating Louisa Chirico of the US 6-0, 7-6 (3).

The Czech Republic's Karolina Pliskova, who is seeded 16th, knocked off Ena Shibahara of Japan 7-5, 6-2.

Elsewhere, Sloane Stephens of the US edged countrywoman Ann Li 7-5, 6-4, and Canada's Leylah Fernandez breezed past American Asia Muhammad 6-1, 6-3.

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Other winners were Taylor Townsend, Hailey Baptiste and Alycia Parks of the US; Eugenie Bouchard of Canada; Dayana Yastremska of Ukraine; Martina Trevisan of Italy; Cristina Bucsa of Spain; and Aliaksandra Sasnovich of Belarus.

None of the day's 14 matches went to a third set.