No.4 seed Ons Jabeur needed five match points to quell the challenge of Lucia Bronzetti in the second round of the Bank of Communications Zhengzhou Open, advancing 6-3, 7-6(5) in 1 hour and 58 minutes.

Jabeur led 5-2 in the second set, and failed to serve out the match three times before coming from 4-2 down to edge the tiebreak. The result was Jabeur's second victory over Bronzetti this year, having also defeated the Italian 6-4, 6-1 in the first round of Roland Garros.

However, the Tunisian was forced to withdraw from her eighth quarterfinal of the year due to a knee injury.

"I'm so sorry that I have to withdraw because my knee is not feeling so great, and I just want to say I loved my time in Zhengzhou," Jabeur said in a statement.

Daria Kasatkina will advance to the semifinals via walkover after the No.8 seed worked hard to close out wild card Bai Zhuoxuan 6-2, 6-4.

Highlights: Kasatkina d. Bai

Kasatkina led 5-2 in the second set, but became tentative in longer rallies as No.117-ranked Bai began painting the lines with winners. The Chinese player held four break points to level at 5-5 before netting a forehand on Kasatkina's fourth match point.

How Jabeur defeated Bronzetti: In the first set, Jabeur was clutch rather than clinical. The first seven games of the match all contained at least one break point, five of which were converted. But despite every game going down to the wire, Jabeur emerged from that passage of play with a 5-2 lead.

The second set was initially more straightforward as Jabeur pulled out to a 5-2 lead, saving the only break point she faced in that stretch. But a pair of double faults scuppered her first attempt to serve out the match, and presaged a nervy close characterized by cheap mistakes and poor shot selection as Jabeur's unforced error tally mounted to 35.

Serving at 5-4, Jabeur sent a forehand wide on her first match point, and a backhand wide as Bronzetti levelled at 5-5. At 6-5, Jabeur missed three more match points, and after six deuces committed another double fault to lose the game. But in a patchy tiebreak from both, it was the Bronzetti forehand that went awry at the end.

Siegemund claims first win over Samsonova: Earlier, qualifier Laura Siegemund continued the Zhengzhou second round's revenge theme with a 3-6, 6-2, 6-1 upset of No.11 seed Samsonova.

Wednesday had seen Jasmine Paolini take out No.6 seed Caroline Garcia despite having failed to win a set in four previous meetings, and then Zheng score her first win over Sakkari in three attempts. Siegemund had not won a set from Samsonova in either of their two prior encounters, but showed off the full range of her repertoire to overcome the Beijing runner-up.

The 35-year-old German delivered passing shots on the line hit at full stretch, drop shots reflexed off full-power Samsonova drives and delightful touch at net to reel Samsonova in. No.113-ranked Siegemund notched her first Top 20 win on hard courts since defeating Marketa Vondrousova at the 2020 US Open, and advanced to her second quarterfinal of the year. The former World No.27 is guaranteed to return to the Top 100 next week.

No.7 seed Barbora Krejcikova opened her Zhengzhou campaign with a 7-5, 6-1 defeat of Petra Martic to reach her fourth quarterfinal of 2023.

Hot shot reel: Siegemund scores first win over Samsonova in style