No.4 seed Ons Jabeur of Tunisia continues her stretch of good form on the green clay of South Carolina, advancing to the Credit One Charleston Open quarterfinals with a 6-3, 6-2 win over Irina-Camelia Begu of Romania.

After just an hour and nine minutes, World No.10 Jabeur picked up her second win in two meetings with 66th-ranked Begu. It was her second victory of Thursday; Jabeur won four points earlier in the day to finish off an interrupted second-round match against Emma Navarro.

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"Very long day, you know," Jabeur said afterward. "I'm glad that I finished quick in the morning. And tonight was really tricky. She was making a lot of mistakes, and then all of a sudden a lot of winners. So to kind of adapt to that kind of changes, it was a little bit tough. But I'm glad that I really won my serve at the end."

Jabeur is 10-2 in Charleston over this season and last season. In 2021, she reached the semifinals of the Credit One Charleston Open, and followed up by making the final of the WTA 250 event at the same site the next week.

Read more: 'I want to be in the Top 5': Ons Jabeur working hard to achieve her goals

Jabeur dropped serve just once in Thursday's night match, while also collecting 61 percent of points returning the Begu second serve. Begu nearly got her second break of the day in the last game of the match, but Jabeur fended off three break points in that game before closing out the win.

In the quarterfinals, Jabeur will take on Ukraine's Anhelina Kalinina for the first time. Kalinina booked a spot in the quarterfinals with a 7-6(5), 7-5 win over No.12 seed Alizé Cornet of France.

Kalinina took just over two hours to earn her second upset of a seeded player this week. 42nd-ranked Kalinina shocked No.5 seed Elena Rybakina in the previous round, notching her first win over a Top 20 player in the process.

Alexandrova takes out Pliskova

Ekaterina Alexandrova swept to a 6-3, 6-1 upset of No.3 seed Karolina Pliskova in the nightcap on Credit One Stadium. The World No.54 needed just 62 minutes to earn the eighth Top 10 victory of her career.

Pliskova had beaten Alexandrova in their two previous meetings. But the Czech, who won her first match of the year this week after hand injury struggles, was unable to capture another win over Alexandrova.

Alexandrova was pristine on serve during the tilt, winning 23 of her 26 first-service points (88 percent) and never facing a break point. Alexandrova took the first break of the match at love for a 4-3 lead and eased to victory from there.

Magda Linette awaits Alexandrova in the quarterfinals. Linette, who gritted out a tough upset win over No.7 seed Leylah Fernandez earlier on Thursday, won her second three-setter of the day in the evening when she bested Kaia Kanepi 6-3, 4-6, 6-2.