INDIAN WELLS, CA, USA -- Top seed Wang Qiang of China eased into the quarterfinals of the Oracle Challenger Series Indian Wells, a WTA 125K Series event, with a 6-1, 6-4 victory over former junior Wimbledon champion Claire Liu of the United States on Thursday.

World No.18 Wang, who took a wild card into the event, broke 18-year-old Liu six times during the 87-minute encounter. Liu fought back from a 5-1, double-break deficit in the second set to get her first two service breaks of the match, and pull back on serve at 5-4. Wang, however, was able to break for the win and move into a quarterfinal match with Kristyna Pliskova of the Czech Republic. 

No.8 seed Pliskova, the left-handed twin sister of former World No.1 Karolina, claimed her quarterfinal win in straight sets over an American as well, moving past Kristie Ahn, 6-1, 7-6(2) in 84 minutes. Pliskova boomed nine aces and won 76 percent of points on her first serve during the clash. Pliskova beat Wang in their only prior meeting, on clay in Prague last year.

Meanwhile, No.10 seed Jessica Pegula of the United States, who clinched a wild card for next week's BNP Paribas Open at Indian Wells after her second-round victory, lost her third-round match to No.6 seed Sara Sorribes Tormo of Spain, 6-2, 6-2.

Former World No.9 Timea Bacsinszky of Switzerland, who executed narrow escapes in the first two rounds against Cori Gauff and former World No.10 Kristina Mladenovic, was less fortunate in another nail-biter, as she was ousted by American Francesca Di Lorenzo, 1-6, 6-2, 7-6(4), after a grueling two hours and 47 minutes.

No.2 seed Alison Riske of the United States was upset, falling to compatriot Jennifer Brady, 6-3, 7-6(4). Brady has been in fantastic form of late -- she made a return to the Top 100 on Monday after reaching the round of 16 at the Premier event in Dubai, where she narrowly fell to eventual finalist Petra Kvitova.

Nicole Gibbs beat a seed in another all-American affair, dispatching No.9 seed Taylor Townsend, 6-1, 6-1. It was one-way traffic for Gibbs, who converted all five of her break points, staved off the two break points she faced, and won a whopping 85 percent of points on her second serve as she rolled past Townsend in just 54 minutes.

Also, No.11 seed Zarina Diyas of Kazakhstan beat 7th-seeded Kaia Kanepi of Estonia, a six-time Grand Slam quarterfinalist, 6-3, 7-6. And No.14 seed Viktorija Golubic of Switzerland defeated 17-year-old American Catherine McNally, 7-6(4), 6-1.

In the quarterfinals, Wang will take on Pliskova, Diyas will meet Di Lorenzo, Golubic will square off against Sorribes Tormo, and Brady and Gibbs will battle in another all-American tilt.