Caroline Wozniacki became the first woman to record 40 wins on the WTA Tour in 2017 by beating Viktorija Golubic at the Ericsson Open.
World number six Wozniacki, the top seed in Bastad, won 6-2 2-6 6-4 to set up a quarter-final clash against Ukrainian qualifer Kateryna Kozlova, who overcame former champion Mona Barthel 6-3 6-3.
Spain's fifth seed Carla Suarez Navarro bowed out of the tournament after a marathon three-set defeat to Belgium's Elise Mertens, who triumphed 6-3 6-7 (2/7) 7-5 in nearly three hours.
Czech Republic's Barbora Krejcikova is through to the last eight after being handed a walkover against sixth seed Kiki Bertens.
Lu Jingjing reached the quarter-finals of the Jiangxi Open in Nanchang after recovering from a set down to beat Jelena Jankovic 2-6 6-1 6-2.
Jankovic struggled in temperatures reaching 39C and called for a trainer during one changeover when a medical timeout was called before play resumed after a 10-minute delay.
Lu will face Nao Hibino for a place in the semis. Japan's Hibino progressed after third seed Karolina Pliskova was forced to retire due to a hand injury as she trailed 3-0 in the opening set.
Second seed Peng Shuai also went through after her opponent retired, with Tereza Martincova unable to continue with the score at 6-2 3-2 against her.
Peng Shuai now faces Zhu Lin, who went through to the last eight after beating Xun Fangying 6-3 6-4, while Wang Yafan overcame Chang Kai-chen 6-0 6-2.
Source: PA
