Tokyo - China's Zhang Shuai became the latest seed to exit the Japan Women's Open on Thursday when she was ambushed by Kazakh qualifier Zarina Diyas.
The 23-year-old Diyas, ranked 72 places below Zhang at 100th in the world, thrashed the second seed 6-4, 6-2 in Tokyo, meaning only two of the top eight-ranked players in the tournament have survived to reach the quarter-finals.
Eighth seed Yulia Putintseva made it a red letter day for Kazakhstan against Chinese opponents by ousting Han Xinyun, who retired with a hip injury when trailing 6-2, 2-0.
As Japanese organisers rue the loss of six seeds and local favourite Kimiko Date in her final tournament at the age of 46, Croatian Jana Fett backed up her upset win over France's top seed Kristina Mladenovic by crushing Slovakia' Jana Cepelova 6-0, 6-3.
In other matches, Wang Qiang restored a measure of pride for China with a 6-2, 6-3 victory over Japan's Kurumi Nara while American Christina McHale overpowered Spain's Sara Sorribes 6-1, 6-1.
Results of singles matches at the WTA Japan Women's Open in Tokyo on Thursday (x denotes seeding):
Jana Fett (CRO) bt Jana Cepelova (SVK) 6-0, 6-3
Yulia Putintseva (KAZ x8) bt Xinyun Han (CHN) 6-2, 2-0 retired
Zarina Diyas (KAZ) bt Shuai Zhang (CHN x2) 6-4, 6-2