Venus Williams kept up with sister Serena by winning a third-round match at the Family Circle Cup, moving one step closer to an all-Williams semifinal. Venus and Serena both reached the quarterfinals of the Family Circle Cup Thursday with straight-set victories. Venus defeated Anastasia Rodionova 7-5, 6-2 on center court shortly after Serena ousted Marina Erakovic, 6-2, 6-2. Should the sisters win on Friday, it would set up a Saturday showdown in the semifinals. “If we both get to the semifinal,” Venus said, “I guess the best Williams will win.” Most times, that's been Serena, who holds a 13-10 edge in the family rivalry – although the two haven't faced each other since Serena took the title at the 2009 WTA Championships in Qatar. Serena holds a 7-5 advantage over her older sister at grand slam events and has won six of the eight times the two have played with a major title on the line. Serena also wasn't yet prepping to face the player on tour she knows the best, although she was rooting for the matchup. “I have to win another match,” Serena said. “I really hope we both get there, so we'll see.” Serena Williams, ranked 10th in the world, might have the easier time of it. She'll go up against 2009 Family Circle winner Sabine Lisicki, who stands 13th in the WTA rankings. The last time the two met, Williams won on the way to the Bank of the West title last summer. “It can only get better,” said Lisicki, the tournament's sixth seed. Venus, who is ranked at No. 87, hadn't played in more than six months until last week's Sony Ericsson Open due to complications from Sjogren's syndrome, an autoimmune disorder. She could face the Family Circle's No. 2 seed and reigning US Open champion Samantha Stosur. Stosur's match with Galina Voskoboeva Thursday night was suspended until Friday when thunderstorms hit the tennis center. Stosur was ahead 4-2 in the first set. Serena will next meet big-hitting German Sabine Lisicki who rallied from a break down in both sets to beat Kazakhstan's Yaroslava Shvedova 7-5, 6-4. Marion Bartoli, the third seed from France, was toppled 6-4, 1-6, 6-4 by 14th-seeded Polona Hercog of Slovenia. Hercog set up a quarterfinal clash with Russian Nadia Petrova, a 6-1, 6-4 winner over eighth-seeded Anastasia Pavlyuchenkova of Russia. Fourth-seeded Russian Vera Zvonareva and Czech ninth seed Lucie Safarova set up a quarterfinal match-up. Zvonareva beat Switzerland's Stefanie Voegele 5-7, 6-3, 6-4 and Safarova defeated Canadian Aleksandra Wozniak 6-2, 6-7 (4-7), 6-1.