CHARLESTON, S.C. — World No. 1 Ashleigh Barty continued her quest for a second straight title, rallying past Shelby Rogers to reach the quarterfinals at the Volvo Car Open on Thursday night.

The top-seeded Barty hadn't played in an 11-month stretch from Feb. 2020 until the Yarra Valley Classic in Melbourne, Australia in January due to the coronavirus pandemic. She's gone 18-2 since her return with a pair of championships including last week's Miami Open.

Rogers, the 28-year-old from nearby Mount Pleasant, South Carolina, gave Barty a challenge, charging from behind to win the second set and tying things at 4-all in the third.

But the Australian won the last two games to close out the match, 7-6 (3), 4-6, 6-4, at the season's first clay-court event.

“It has been a very quick turnaround,” she said of changing surfaces. “I'm still allowing myself time to get used to that. But with each match, that will get better and better.”

Barty will face Paula Badosa of Spain on Friday for a spot in the semifinals. Badosa defeated American Catherine McNally 6-3, 6-3.

Barty is the only one of the top eight seeds still around.

Others in the final eight include former U.S. Open champion Sloane Stephens, who hadn't advanced to a tournament quarterfinals since the French Open in 2019.

Stephens, the American who won her grand slam title in 2017, ousted Australia's Ajla Tomljanovic 6-3, 6-4. Stephens will play for a spot in the semifinals against Russian Veronika Kudermetova. Kudermetova, seeded 15th in the season's first clay-court event, topped Kurumi Nara of Japan 6-0, 6-3.

Stephens had been on a slide the past two seasons, falling from No. 3 in the world to 57th entering this event. But she's won three times here, winning 11 of the final 12 points against Tomljanovic.

Things are starting to come together, Stephens said.

“Just getting my competitiveness back, I think, makes me happy,” she said. “And being able to fist pump without fighting my own brain, it's nice.”

Also reaching the quarters is the youngest competitor here in 17-year-old American Coco Gauff, the 14th seed who defeated countrywoman Lauren Davis 6-2, 7-6 (2).

Gauff has advanced to the quarterfinal round in three of last four tournaments. She said when she lost several points in a row in the second set against Davis, she snapped herself back into the match.

“I try and keep track of that because sometimes you lose focus for 10-15 minutes and that's three or four games,” she said.

Two-time Wimbledon champion Petra Kvitova, seeded third, fell to Danka Kovinic of Montenegro, 6-4, 6-1.

The sixth seed, Garbine Muguruza of Spain, was ahead in her match with Yulia Puntintseva of Kazakhstan before retiring with a left leg injury.