Reigning champion Venus Williams joined top seed Angelique Kerber in being dumped out of the Wuhan Open on Wednesday.
Williams was comfortably seen off in straight sets by ninth seed Svetlana Kuznetsova to end her challenge in China, while world number one Kerber lost a marathon encounter with Petra Kvitova.
Kuznetsova and Kvitova join Johanna Konta, Simona Halep, Madison Keys and Agnieszka Radwanska in the quarter-finals.
However, two other last-16 matches were halted by rain.
WILLIAMS WOE, KERBER STUNNED
Williams, seeded sixth, never got going against her Russian opponent, who prevailed 6-2 6-2.
Kuznetsova took the opening set in just 29 minutes, serving it out to love to underline her dominance.
The trend continued in the second set, as Williams was broken at the first two opportunities and could muster no meaningful response.
Kerber needed nearly an hour and a half to win the first set against Kvitova, but that was as good as it got, with the Czech emerging a 6-7 (10-12) 7-5 6-4 victor after more than three hours.
KONTA CONTINUES TO BOOST FINALS HOPES
Briton Konta is seeking a spot at the season-ending Tour Finals, meaning her 7-5 7-6 (8-6) victory over Carla Suarez Navarro was particularly sweet.
Fellow seed Simona Halep also made it through, the Romanian proving too strong for Yaroslava Shvedova in a straight-sets success.
Madison Keys was taken the distance before overcoming Daria Kasatkina 6-1 4-6 6-4.
The final match saw Radwanska put a halt to Caroline Wozniacki's recent resurgence in a dominant 6-4 6-2 victory.
Wozniacki reached the semi-finals of the US Open and was a victor in Tokyo last week where she beat Radwanska in the semi-finals, but on this occasion it was the Pole who came out on top.
RAIN HALTS PLAY
Play was suspended on Court One on Wednesday owing to rain, with Karolina Pliskova versus Dominika Cibulkova, and Barbora Strycova against Jelena Jankovic the matches affected.