No 1 seed Zheng Qinwen of China swept the last nine games against Japan's Moyuka Uchijima on Thursday to move into the Toray Pan Pacific Open quarterfinals in Tokyo.

Trailing 5-4 in the first set, Zheng rolled to a 7-5, 6-0 victory in 77 minutes. The reigning Olympic gold medalist will next face No 8 seed Leylah Fernandez of Canada.

Third-seeded Daria Kasatkina of Russia rallied for a 3-6, 6-3, 6-1 win over McCartney Kessler. Kasatkina will take on Sofia Kenin, who outlasted Denmark's Clara Tauson 6-7 (8), 6-4, 7-6 (6) in 2 hours and 51 minutes. No 9 seed Katie Boulter of Great Britain crushed Japan's Kyoka Okamura 6-1, 6-2 in 69 minutes.

Guangzhou Open

Top-seeded Czech Katerina Siniakova avoided the upset bug with a swift 6-1, 6-4 victory against Alycia Parks in China.

Siniakova saved all seven break points she faced and converted four of five break chances in the 78-minute win. Her opponent in the quarterfinal will be Bernarda Pera, who rolled to a 6-2, 6-2 win against China's Zhang Shuai.

READ MORE: China's Zhang Shuai, Wang Xiyu eliminated in Wuhan Open first round

Siniakova's compatriot, No 2 seed Marie Bouzkova, was not as fortunate and lost to Caroline Dolehide 6-7 (3), 6-4, 7-6 (6) in 3 hours and 18 minutes. Thailand's Manachaya Sawangkaew wiped out No 3 Yuan Yue of China 6-2, 6-3 in just 67 minutes.