India's Sania Mirza shocked fifth-seeded Russian Anastasia Pavlyuchenkova 7-6(3), 3-6, 6-2 for a place in the quarter-final of the Aegon Classic tennis in Birmingham.
The 22-year-old Hyderabadi, who sent the Briton Anne Keothavong packing in the previous round, Thursday doled out yet another impressive performance against the World No. 31 Russian.
The 17-year-old Pavlyuchenkova had staved off a gritty challenge from Elena Baltach of Britain in a tough three-setter earlier in the day to reach the third round.
Sania, who in February reached her second WTA final in two years at the Pattaya Open, now plays Hungary's 16th seed Melinda Czink.
Czink, ranked 62, upset third seed Aleksandra Wozniak of Canada 6-7 (7), 7-5, 7-5.