"Unfortunately I am no longer able to train and play the way I used to, and recently my body can't live up to my expectations," Radwanska, 29, said in a post on Facebook.
Former French Open champion Jelena Ostapenko is the latest player to withdraw from the US Open, organisers of the tennis Grand Slam confirmed on Monday.
Madison Keys swept past Wimbledon champion Elena Rybakina 6-2, 6-4 at the Cincinnati Open on Friday, setting up a semi-final clash with Petra Kvitova after the Czech defeated Ajla Tomljanovic.
Swiatek's last defeat on clay came in the WTA 1000 event in Madrid against Australian Barty, who elected not to defend her 2019 French Open title last year due to the COVID-19 pandemic.
Raducanu retires in Rome as back injury persists, Jabeur survives early scare
It will be 'Mother's Day' on Wimbledon's Centre Court on Monday when Serena Williams takes on fellow mum Evgeniya Rodina for a place in the quarter-finals of the grasscourt major.
On the men's side, the fields have already been divided into two ATP 250 tournaments.
Russian player Yana Sizikova has been released from police custody a day after being arrested at the French Open over match-fixing allegations related to last year's tournament, her lawyer said on Friday.
Williams posted pictures on her Instagram page and wrote: Caption this (MUST SWIPE RIGHT).
Sania Mirza continued her winning run as she entered the women's doubles semifinals of the Hobart International
Hubert Hurkacz showed his Wimbledon credentials on Sunday, hammering world number one Daniil Medvedev
Perry said she had been in touch with the local organising team on a daily basis as they prepare to start the tournament on October 19, pending government approval and confirmation that players will be able to travel.
Indian tennis player Sania Mirza on broke into the doubles top-10 for the first time in her career as she gained a place after the US Open, where she made the third round along with Russian partner Elena Vesnina.
Barty is primed to become the first local since Chris O'Neil in 1978 to win the Australian Open.
Serena Williams' tactic of staying in her hotel room and being "boring" appears to be paying off after the world number one and top seed swept past Sara Errani into the final of the Madrid Open on Saturday.
The Pole said she wanted to do better this time and felt the pressure.
Garbine Muguruza was relieved to finally avoid tripping at the last hurdle and end her trophy drought
Serena Williams shook off some COVID-19 layoff rust to grind out a 7-6(6), 3-6, 7-6(0) win over Dutch qualifier Arantxa Rus on Monday to move into the third round of the Western and Southern Open.
Former world number 11 Shahar Peer, the most successful Israeli woman to play on the WTA Tour, announced her retirement because of injury on Tuesday.
Wawrinka splits with long-time coach Norman
A summary of Tuesday's action at the US Open.
Bianca Andreescu is the first Canadian to win a major in the professional era.
The International Tennis Federation (ITF) has said it is working on additional measures, including a new relief fund, to support lower-ranked professionals who have been left in the lurch due to coronavirus-led lockdowns.
Indian tennis ace Sania Mirza and her Swiss partner Martina Hingis lifted their ninth title together this year beating the Spanish pair of Garbine Muguruza and Carla Suarez Navarro to clinch the WTA Finals women's doubles trophy, in Singapore, on Sunday.
New mum Victoria Azarenka wants to see more child-friendly tournaments on the WTA Tour, saying not enough is done to help players travelling with young families.
Naomi Osaka was beaten 6-0, 6-4 by Greek 23rd seed Maria Sakkari.
The video has already garnered over 3.85 million views and shows Federer hitting between-the-legs "tweeners" and behind-the-back shots.
Serena said she felt 'pretty fresh' ahead of the claycourt swing as she prepares for the French Open
Last week the men's ATP and the WTA, which runs women's events, issued revised calendars for the resumption of the circuit from August while organisers of the US Open said the Grand Slam will be staged without fans as scheduled from August 31 to September 13 in New York.
All players who want a visa to compete in the Australian Open will need to be fully vaccinated for COVID-19, the country's immigration minister said on Wednesday, putting Novak Djokovic's title defence and Grand Slam record bid in doubt.
Andy Murray took a step closer to a first title in arguably the toughest year of his playing career, grinding out a 3-6, 7-5 ,6-2 win over Ugo Humbert on Saturday to reach the final of the European Open in Antwerp.
Factbox on Romanian Simona Halep, who beat Sloane Stephens 3-6, 6-4, 6-1 to win the French Open title on Saturday:
Pavlyuchenkova finally reached a Grand Slam final in her 52nd appearance
Petra Kvitova takes on Naomi Osaka in Saturday's Australian Open final with one of them set to emerge as a fresh champion at Melbourne Park.
A look at the records of Czech Republic's Karolina Pliskova and Japan's Naomi Osaka before their semi-final match at the Australian Open on Thursday (prefix number denotes seeding):
Former champions Novak Djokovic, Rafael Nadal and Serena Williams have all entered next month's Western & Southern Open in New York, which will serve as a tune-up for the US Open, tournament organisers said on Wednesday. Organisers of the August 20-28 event, which was relocated from Cincinnati this year because of COVID-19, said defending champions Daniil Medvedev and Madison Keys are also among the initial entries.
IMAGES from Day 7 of the matches played at the US Open at Flushing Meadows on Sunday.
Osaka had pulled out of the French Open citing mental health and revealed that she suffered long bouts of depression since the US Open in 2018.
The decision marks Clijsters' second return to the sport after first retiring in 2007.
Halep reached the Melbourne title match in 2018 but lost a three-set thriller to Caroline Wozniacki. It was the Romanian's third defeat in three Grand Slam finals.