In the women's semifinals on Saturday, Petrova topped No. 8 Nicole Vaidisova of the Czech Republic, 6-0, 4-6, 7-6 (7-3).
"We were both getting a little tight at the end," Petrova said. "It was a matter of who could keep the ball in. After I had those match points I told myself I'm still in with a very good chance to win; my experience helped me through in the end."
Chakvetadze continued her surprising run with a 7-5, 3-6, 6-0 win over fourth-seeded Elena Dementieva, also a native Russian.
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