Dallas - Second-seeded Jelena Jankovic and No 3 Roberta Vinci advanced to the quarter-finals on Tuesday at the WTA Texas Open, a tune-up event for next week's US Open in New York.
Jankovic, the former world number one from Serbia, defeated Arantxa Rus of the Netherlands 7-6 (7/5), 6-2 to line up a quarter-final clash against eighth-seeded Sorana Cirstea of Romania, a 6-1, 7-5 winner over France's Alize Cornet.
Italy's Vinci encountered little resistance in a 6-2, 6-3 victory over Slovakia's Polona Hercog. She'll face seventh-seeded Chanelle Scheepers of South Africa, who beat New Zealand's Marina Erakovic 6-4, 7-6 (7/3).
Vinci, who won the last three games to close out her match, said she was feeling confident with the US Open due to start on Monday on the hard courts of Flushing Meadows.
"I played good tournaments in Montreal and Cincinnati," Vinci said. "I like to play on hard courts. I like to play on fast courts. I play a lot of slice, probably that's why I play on fast courts.
"I won (Monday) 6-2, 6-2. I won (Tuesday) 6-2, 6-3, so for sure, I'm confident, and we will see tomorrow," she said. "But I am confident going into the US Open."
Fourth-seeded Belgian Yanina Wickmayer was a second-round casualty, falling to Australian Casey Dellacqua 6-4, 6-3.
Dellacqua, a qualifier, will face unseeded Canadian Aleksandra Wozniak who beat compatriot Eugenie Bouchard 6-2, 6-2.
Sixth-seeded Peng Shuai of China moved safely through with a 6-4, 6-2 victory over France's Pauline Parmentier.
Peng will face wild card Bojana Jovanovski of Serbia, who beat Croatian Mirjana Lucic 7-6 (7/5), 6-2.
Results from the WTA Tour's Texas Open on Tuesday (x denotes seeding):
Bojana Jovanovski (SRB) bt Mirjana Lucic (CRO) 7-6 (7/5), 6-2
Peng Shuai (CHN x6) bt Pauline Parmentier (FRA) 6-4, 6-2
Roberta Vinci (ITA x3) bt Polona Hercog (SLO) 6-2, 6-3
Chanelle Scheepers (RSA x7) bt Marina Erakovic (NZL) 6-4, 7-6 (7/3)
Aleksandra Wozniak (CAN) bt Eugenie Bouchard (CAN) 6-2, 6-2
Casey Dellacqua (AUS) bt Yanina Wickmayer (BEL x4) 6-4, 6-3
Sorana Cirstea (ROM x8) bt Alize Cornet (FRA) 6-1, 7-5
Jelena Jankovic (SRB x2) bt Arantxa Rus (NED) 7-6 (7/5), 6-2