NEW YORK, United States (AFP) — Spanish ninth seed Garbine Muguruza outlasted 18th seed Victoria Azarenka of Belarus yesterday at the US Open in a showdown of two-time Grand Slam champions and former world number ones.

Muguruza matched her best US Open showing from 2017 by defeating three-time US Open runner-up Azarenka 6-4, 3-6, 6-2 in the only Slam where the Spaniard hasn’t reached the final.

“It’s a Grand Slam where I’ve been struggling,” Muguruza said. “This year it’s working so I want to keep going.”

Muguruza broke at love in the ninth game of the first set and held to grab the lead, then won after two hours and 15 minutes as Azarenka double-faulted.

“Playing on this court in front of this crowd against Vika, it’s the perfect scenario,” Muguruza said. “Playing the whole year without crowd, this is super amazing. I feel pumped.”

Romanian 12th seed Simona Halep, a two-time Grand Slam champion battling back after an injury layoff, ousted 19th seed Elena Rybakina of Kazakhstan 7-6 (13/11), 4-6, 6-3 after two hours and 25 minutes.

“Definitely, it has been a very tough match,” Halep said. “I knew she was very powerful. I knew I had to be strong. I knew I had to be calm but I didn’t.”

Former number one Halep, her right thigh taped after an injury two weeks ago, failed on six set points before Rybakina, who lost four set points herself, double faulted to end a 17-minute tie-breaker and drop the first set after 64 minutes.

Rybakina forced a third set but Halep held firm for the win.

“I just said I have to fight back and I did,” said Halep, who says she’s “still far” from peak form.

“Every day I’m building my confidence,” she said. “It’s not easy to be out for several months and then come back and play the matches.

“I’m focused every day. I know it’s going to be a tough battle but I have nothing to lose. It’s about enjoying the tennis and the fact I’m healthy and can play again.”

Defending champion Naomi Osaka was set to face Canadian teen Leylah Fernandez in an Arthur Ashe Stadium night match.

Osaka seeks her fifth Grand Slam title, her third US Open crown in four years and could become the first back-to-back US Open winner since Serena Williams won her third in a row in 2014.

It would be Osaka’s fourth-straight trip to the US Open’s last 16 and stretch her Grand Slam win streak to 17 matches.

Second seed Arnya Sabalenka of Belarus was set to play US 26th seed Danielle Collins, whom she beat here in 2018.

Greek third seed Stefanos Tsitsipas was set to face 18-year-old Spaniard Carlos Alcaraz, who could become the youngest player into the US Open fourth round since 17-year-old American Michael Chang in 1989 or at any Slam since Ukraine’s Andrei Medvedev in the 1992 French Open.

French Open runner-up Tsitsipas seeks his first trip to the US Open’s fourth round, which would give him trips to the last 16 at every Slam.

Alcaraz, the youngest player this deep at a US Open since 2007, has matched his best Slam showing from the third round at this year’s French Open.

Alcaraz, ranked 55th, would be the youngest man to beat a top-3 player at the US Open since the rankings began in 1973 and to do so anywhere since Denis Shapovalov beat then-number two Rafael Nadal in 2017 at Montreal.

Russian second seed Daniil Medvedev, the 2019 US Open and 2021 Australian Open runner-up, was to face Spain’s 74th-ranked Pablo Andujar, who was trying to match his deepest Slam run from the 2019 US Open.

Russian fifth seed Andrey Rublev, never past the quarter-finals in any Slam, had a night match against 50th-ranked Frances Tiafoe, who won their only prior meeting in the 2014 US Open boys quarter-finals.

Tiafoe is trying to become the first American into the US Open fourth round in consecutive years since 2012.