Top-seed Jelena Jankovic and second seed Caroline Wozniacki have suffered surprise third-round exits in the Cincinnati Tennis Open.
In fierce heat, the Serbian Jankovic lost to Akgul Amanmuradova 7-6 6-4, with the Uzbeki qualifier now set to face another Serb, Ana Ivanovic.
A lesser shock, but a surprise nonetheless, was Dane Wozniacki falling to France's Marion Bartoli 6-4 6-1.
Completing a trio of upsets, Russian sixth-seed Vera Zvonareva went out in straight sets, 6-4 6-3 to Italian Flavia Pennetta.
Eighth-seeded Na Li of China also suffered a premature departure, losing to Belgian Yanina Wickmayer 2-6 6-2 7-6 in an exciting three-set encounter.
However the unseeded Ivanovic again looked in good form as she confidently defeated Russia's Elena Vesnina 6-love 6-3.