Elina Svitolina made up for a sluggish start by beating Dalila Jakupovic in straight sets at the Guangzhou Open but second seed Wang Qiang crashed out.
World number three Svitolina, who reached the semi-finals of the US Open, dropped her serve in the opening game of her first-round clash before reeling off five in succession en route to taking the set.
The top seeded Ukrainian fended off four break points to consolidate starting the second with a break, but she was unable to serve out the match at the first attempt.
Svitolina responded immediately, though, breaking to complete the 6-3 6-3 triumph in just 69 minutes and setting up a meeting with Marie Bouzkova.
Wang saved four match points against Shuai Peng but was unable to join Svitolina in the second round.
Although Wang moved ahead of Shuai with four breaks across the match, she got only 43 per cent of her first serves in and won just 54% of points behind it in a 7-5 6-2 loss.
Katarina Zavatska came from behind to defeat Fiona Ferro 5-7 7-6 (8-6) 6-4 in three hours and 27 minutes – the longest WTA Tour main-draw match of the year.
Sofia Kenin, Zhang Shuai, Katerina Siniakova and Zheng Saisai were the other seeds to advance.
At the Korea Open, Patricia Maria Tig made the most of top seed Maria Sakkari's withdrawal due to a right wrist injury by defeating lucky loser Danka Kovinic 6-4 3-6 7-6 (7-3).
Jelena Ostapenko, the champion in 2017, fell 6-3 6-3 to Timea Babos, while sixth seed Polona Hercog went down 6-3 3-6 6-1 against Ana Bogdan.
There were also wins for Karolina Muchova and Ajla Tomljanovic, seeded third and fifth respectively.