China's Olympic champion Zheng Qinwen survived a scare at her home China Open in defeating the 43rd-ranked American Amanda Anisimova 3-6, 6-1, 6-2.

Zheng faces the Russian 17-year-old Mirra Andreeva in the quarter-finals.

It kept the home hero on course to meet world number two Aryna Sabalenka in a blockbuster last-four showdown.

The top seed kept up her side of the bargain with a ruthless 6-4, 6-3 victory over another American in Madison Keys.

US Open champion Sabalenka next plays Karolina Muchova of the Czech Republic. (AFP)