After sixth-seeded Maria Sakkari of Greece pulled out due to injury shortly before her match on Tuesday, American teenager Coco Gauff stepped in as a lucky loser and advanced to the second round at the Upper Austria Ladies Linz.

Gauff, 15, beat Switzerland's Stefanie Vogele 6-3, 7-6 (3) in a little over two hours, a day after falling in the second round of qualifying. The tournament is Gauff's first action since losing to then-world No. 1 Naomi Osaka of Japan in the third round of the U.S. Open.

Meanwhile, Anna-Lena Friedsam of Germany engineered a major first-round upset, taking down second-seeded Swiss Belinda Bencic 6-4, 2-6, 6-2. Friedsam, ranked 166th in the world, downed the world's 10th-ranked player in 1 hour and 52 minutes despite falling behind 4-0 in the opening set.

Fourth-seeded Donna Vekic of Croatia had no such trouble, cruising by Slovenia's Polona Hercog 6-1, 6-1 in just 50 minutes. German fifth seed Julia Goerges also advanced in straight sets, beating Russia's Margarita Gasparyan 6-4, 6-2.

Seventh-seeded Barbora Strycova of the Czech Republic fell 6-4, 6-4 to Frenchwoman Alize Cornet.

Tianjin Open

Second-seeded Qiang Wang delighted the home crowd with a 6-3, 6-4 victory over Australia's Arina Rodionova to reach the second round in Tianjin, China.

Wang overcame six double faults in victory, saving four of six break points.

All other seeded players in action advanced in straight sets, with No. 3 Dayana Yastremska of Ukraine beating China's Lin Zhu 6-2, 6-3; No. 7 Saisai Zheng of China downing countrywoman Yingying Duan 7-6 (4), 6-2; and No. 8 Magda Linette of Poland dispatching American Christina McHale 6-3, 6-1.

--Field Level Media

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