Zhang bundled out in Tokyo
There was an upset at the Japan Women's Open Tennis as second seed Zhang Shuai lost to qualifier Zarina Diyas on Thursday.
Zhang made the third round of the US Open recently, but she went down 6-4 6-2 in Tokyo.
The 28-year-old - a quarter-finalist at the 2016 Australian Open - hit five aces but she came unstuck on her second serve, only winning 32 per cent compared to Diyas' 72.
While Zhang departed the WTA International tournament, eighth seed Yulia Putintseva advanced past the last 16.
World number 52 Putintseva triumphed 6-2 2-0 after Han Xinyun retired.
Meanwhile, Jana Fett's run continued following her straight-sets win over Jana Cepelova.
Fett sprung a surprise on Wednesday when she eliminated top seed Kristina Mladenovic in the opening round and the qualifier backed that up with a 6-0 6-3 victory.
Christina McHale cruised past Sara Sorribes Tormo 6-1 6-1 and Kurumi Nara lost 6-2 6-3 to Wang Qiang.