Aryna Sabalenka's mid-game act stuns tennis world at US Open

Aryna Sabalenka has left tennis fans in a frenzy at the US Open after an extraordinary move on break point against Danielle Collins.

Sabalenka bounced back from a slow start and visits from the trainer to beat American hope Collins 3-6 6-3 6-2 on Monday to reach the quarter-finals in New York.

'SO SAD': Rafa Nadal's devastating announcement after loss

'GUTTED TO HEAR': Tennis fans react to sad Novak Djokovic news

The World No.6 from Belarus continued her mastery over Collins at Flushing Meadows, beating her for the third time at the US Open after victories in 2018 and 2021.

She led 4-3 in the second set when she needed a medical timeout, with a trainer massaging her left thigh throughout breaks in the match.

Sabalenka, who made the semi-finals at the US Open last year, said in her on-court interview after the match that she was fine.

There were extraordinary scenes in the second set when Sabalenka decided to change her racquet before a second serve while down a break point.

The Belarusian jogged off court to grab a new racquet before producing an unreturnable serve, saving the break point and going on to hold.

Fans and commentators were left stunned by the bizarre move, with Sabalenka later revealing the racquet felt 'super loose'.

At one point Sabalenka complained to the chair umpire about crowd noise, with plenty of fans once again packed inside Arthur Ashe Stadium.

The US Open has attracted a record attendance figure of 549,657 fans since the main draw started last Monday.

It’s the highest-ever attendance for the tournament through its first eight days, breaking the previous record of 540,333 set in 2019.

Swiatek and Pliskova move into US Open quarter-finals

Sabalenka will next face Karolina Pliskova after the 24th seed earlier moved into the quarterfinals with a 7-5 6-7 (5) 6-2 win over 26th-seed Victoria Azarenka.

Pliskova has returned to form at Flushing Meadows after a broken right wrist forced her to miss the Australian Open and she struggled in her first few tournaments when she returned to action.

Meanwhile, World No.1 Iga Swiatek has set up a quarter-final showdown with Jessica Pegula after overcoming an early deficit to beat Jule Niemeier.

Pegula was up against two-time Wimbledon champion Petra Kvitova, but she brushed her aside 6-3 6-2 to reach her third major quarter-final of 2022.

Swiatek beat Germany's Niemeier 2-6 6-4 6-0, but is clearly not in the form that brought her 37-straight wins earlier this season.

Swiatek came into the US Open just 4-4 in her last eight matches but she hadn't lost a set at Flushing Meadows until Monday.

Niemeier got the early jump - as she exhorted the crowd to get louder - and gamely tried for another grand slam upset and knocking out No.2 seed Anett Kontaveit at Wimbledon.

Swiatek steadied herself in the second set and hit 10 winners, and she turned the third set into a 6-0 rout.

The World No.1 became the first Polish woman to reach the quarterf-inals at the US Open and is trying to become the first top-seeded woman to win it since Serena Williams in 2014.

"I'm just proud that I didn't lose hope because she was playing really good in the first set," she said on court.

"I'm pretty glad that I used my experience to keep the same kind of level throughout the whole match."

with agencies

Click here to sign up to our newsletter for all the latest and breaking stories from Australia and around the world.