The 11th-ranked Serb, looking for her fourth title of the year, will face top-ranked Serena Williams on Friday.
Zhao, a sophomore All-American at Stanford, appeared in her second WTA Tour event and gained her first career win at the level Tuesday when Yanina Wickmeyer retired because of a viral infection.
Ivanovic, a former No. 1, had three aces and won 75 percent of her first-serve points.
- Sports & Recreation
- Ana Ivanovic
- Serena Williams
- Carol Zhao