Sabalenka impresses again, Rybakina and Pegula win; Bergs upsets Mensik as Belgium reach United Cup semis

World number one Aryna Sabalenka said she still had room for improvement after a second dominant win in the Brisbane International on Thursday.

Sabalenka was pushed at times by 36-year-old Sorana Cirstea but was never really troubled by the Romanian as she notched a 6-3, 6-3 win to reach the quarter-finals of the season-opening tournament.

The Belarusian will next play Madison Keys, the American who beat her in last year’s Australian Open final.

Keys came back from a set and a break down to overcome Russia’s Diana Shnaider in a three-hour marathon 6-7 (5/7), 7-6 (7/5), 7-6 (7/4).

There was a shock in the last of the night’s matches when Ukraine’s Marta Kostyuk stunned world number three Amanda Anisimova 6-4, 6-3 in a high-quality match on centre court.

Sabalenka said she aimed to get better as she targets a third Australian Open title in four years when the first Grand Slam of the year begins in Melbourne on January 18.

Sabalenka said tournaments such as Brisbane, which features seven of the top 10 women, were perfect preparation for a Grand Slam.

Keys, who won her first Grand Slam title in Melbourne over Sabalenka, was in trouble against 21-year-old Shnaider but was able to stay in the contest and edge ahead in the last two tiebreaks.

Kostyuk played the match of her life to down Anisimova, who reached the finals of Wimbledon and the US Open in 2025.

Former Wimbledon champion Elena Rybakina reached the quarter-finals with a 6-3, 6-2 win over Spain’s Paula Badosa.

World number five Rybakina took control at 3-3 in the first set, winning nine of the next 11 games to seal victory.

Fourth seed Jessica Pegula also came back from a set down beat Ukraine’s Dayana Yastremska 5-7, 6-2, 6-3.

Meanwhile, Zizou Bergs stunned world number 18 Jakub Mensik and Elise Mertens outplayed Barbora Krejcikova as Belgium beat the Czech Republic 2-0 in the United ‍Cup ‌quarter-finals on Thursday to set up a last-four clash with ‍Switzerland.

Mensik struggled with double faults in the second set as Bergs won 6-2 7-6(4), before former ‍world number one Mertens beat Krejcikova 5-7 6-1 7-5 ‍to seal the tie.

Bergs, ranked 42nd in the world, landed four aces as he took the first set in 31 minutes, and kept his cool through a tense second-set tiebreak to clinch his ‌second straight win over a top-20-ranked opponent, having ‍beaten Canadian world number five Felix Auger-Aliassime in the group stage.

“You’re so close, you’re playing big points. ​I got tight, I go backwards, I play defensive. So it was a very big struggle in the end. ​I’m ‍so happy for myself and the team,” Bergs ‌said.

Mertens wore down two-time Grand Slam winner Krejcikova who committed seven double faults in the third set.

“I felt ​like I ‌had to play a little aggressive... I’m really happy I could turn it around. It was 1-0 for Belgium, so I could play freely, thanks ‌to Zizou,” Mertens said. Australia face Poland on Friday for a place in Saturday’s first semi-final against the United States.

Elsewhere, top-seeded Elina Svitolina again relied on her “fighting spirit” Thursday, beating wild-card entry Katie Boulter 7-5, 6-4 to reach the quarterfinals of the WTA tournament in Auckland, New Zealand.

Both players struggled on serve in windy conditions on center court. There were nine service breaks in the match, which the No. 13-ranked Svitolina clinched on her third match point.

Svitolina dropped her serve in the third game, immediately broke back but was broken again in the ninth. She won some exceptional clutch points to break Boulter again and take the first set.

Svitolina broke Boulter in the fourth game on the second set but immediately dropped serve. Both players had to work hard to hold in the sixth and seventh games before a series of three consecutive breaks which ended with Svitolina’s second singles win in 2026.

Svitolina ended her 2025 season in September when she took a break from the tour for mental health reasons.

The Ukranian star won her opening match in Auckland 6-3, 6-1 over Varvara Gracheva.

The tournament in Auckland is an important tuneup event for the Australian Open, the season-opening major that starts in Melbourne on Jan. 18.

Agencies