MEMPHIS, TN, USA - Midway through the second round just two seeds are still alive at the $220,000 Cellular South Cup, after No.7 seed Renata Voracova fell at the International event on Tuesday.

The Czech, ranked No.83 in the world, didn't hold serve once against 19-year-old Ksenia Pervak, who is currently ranked No.94. The young Russian dropped her own serve twice but advanced to her third WTA quarterfinal in one hour and 15 minutes, 61 61.

In other second round matches, Magdalena Rybarikova won a see-saw battle with former British No.1 Anne Keothavong, 64 36 61. The 105th-ranked Slovak's quarterfinal opponent will be American qualifier Alexa Glatch, who outlasted Dutchwoman Michaella Krajicek, 76(2) 36 63.

While Rybarikova and world No.288 Glatch will be meeting for the first time in the last eight, Pervak awaits the winner of Wednesday's second round encounter between Czech players Sandra Zahlavova and Lucie Hradecka.

Remaining seeds Melanie Oudin (No.3) Rebecca Marino (No.6) both play their second round matches on Wednesday. America's Oudin faces Evgeniya Rodina of Russia, while Canada's Marino - seeded at a tour event for the first time - takes on Sorana Cirstea of Romania.

Oudin is also still in contention in the doubles, after she and fellow teen Jamie Hampton - a wildcard combination - beat experienced Julie Coin and Keothavong in a first round clash, 64 62.