Top seed Justine Henin-Hardenne continued her Family Circle Cup dominance Thursday with a 6-4, 6-4 victory over Croatian baseliner Karolina Sprem.

World number three Henin-Hardenne, eliminated in the first round of her previous tournament at Miami [Images], appeared to gain strength in her second Charleston match to reach the quarter-finals of the event she won in 2003 and 2005.

"I don't have any problems physically," the Belgian told reporters.

"I mean, there are still a few issues with my shoulder but not something major that is bothering me right now."

All the top four seeds advanced Thursday, including Russians Nadia Petrova and Svetlana Kuznetsova and Swiss Patty Schnyder.

Second seed Petrova, coming off a title at Amelia Island last week, overpowered 14th seeded Lucie Safarova of the Czech Republic 6-1, 6-3 to set up a match with Colombia's Catalina Castano, the only unseeded player to reach the quarterfinals.

World number 48 Castano advanced when France's [Images] Marion Bartoli retired with left knee inflammation with Castano leading the 5-4 in the first set.

Kuznetsova, the fourth seed, overcame hip and elbow worries to defeat Lourdes Dominguez-Lino of Spain 6-2, 6-1. She will play sixth seeded Anna-Lena Groenefeld, a 7-6(3), 6-3 winner over Anabel Medina Garrigues.

Third seeded Schnyder defeated Mara Santangelo 3-6, 7-6(2), 6-3 after the Italian played brilliantly in the first set, making only eight unforced errors.

"It was a really big struggle, and I didn't feel comfortable," Schnyder said.

Schnyder on Friday will play France's Nathalie Dechy, the eighth seed. Dechy, finally healthy and playing some of her best tennis of the year, defeated 11th seeded Katarina Srebotnik of Slovenia 6-2, 6-3.

Henin-Hardenne will face Russian Dinara Safina in the quarterfinals. Safina, the seventh seed, ousted qualifier Julia Vakulenko of the Ukraine 6-7(6), 6-2, 6-2.

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