Osaka, Osaka Prefecture, Japan, 11 October 2014 | AAP

Defending champion Samantha Stosur rolled into the semifinals of the Japan Women’s Open on Friday with a clinical 6-4 6-1 victory over Yulia Putintseva of Kazakhstan.

The top-seeded Australian, who won the US Open title in 2011 and reached a career-high fourth in the world, will face Ukraine’s Elina Svitolina in the last four after the No.3 seed blew away American Lauren Davis 6-2 6-4.

Zarina Diyas restored some Kazakh pride by battling to a 6-7 6-4 6-2 win over Croatia’s Ana Konjuh.

She will play Asian Games gold medallist Luksika Kumkhum in Saturday’s semifinals after the Thai knocked out American Madison Keys, who retired hurt while trailing 6-2 4-3.

In Tianjinm, eighth seed Ajla Tomljanovic fell to second seed Peng Shuai 7-6(5) 2-6 7-5 in a match that lasted two-hours and 45 minutes.