Garbine Muguruza beat Kim Clijsters in the Belgian's first match since 2012, but the four-time major champion saw some positives.
Coco Gauff could become the youngest US Fed Cup player since 14-year-old Jennifer Capriati, having been picked alongside Serena Williams.
Ashleigh Barty survived the challenge of Alison Riske, but Coco Gauff's Australian Open campaign was ended by Sofia Kenin.
Donna Vekic and Maria Sakkari's hopes of ending the season on a high note were ended in Zhuhai on Wednesday.
Naomi Osaka made it six wins in succession as world number one Ashleigh Barty and defending champion Caroline Wozniacki triumphed in China.
Alison Riske's run to the final of the Wuhan Open ended in defeat as Aryna Sabalenka won the title for a second straight year.
Aryna Sabalenka lies in wait in the Wuhan Open final for Alison Riske, who fought back past Petra Kvitova in Friday's last-four contest.
Kiki Bertens awaits at the Pan Pacific Open for Anastasia Pavlyuchenkova, who was a round-one winner in Osaka.
Angelique Kerber was knocked out in a first-round thriller at the Zhengzhou Open, but Jelena Ostapenko survived a major scare.
Returning to the scene of her maiden grand slam title, world number one Naomi Osaka outlasted Anna Blinkova in three sets on Tuesday.