Jankovic set up a semifinal meeting with French Open finalist Dinara Safina, the fourth seed. Safina breezed past Victoria Azarenka in the quarterfinals 6-3, 6-1.
Saturday's other semifinal encounter will send Flavia Pennetta against Bethanie Mattek.
Pennetta outlasted Sybille Bammer 7-6 (7-3), 3-6, 6-1 and Mattek was a 6-2, 7-5 winner over Meng Yuan.
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