Iga Swiatek is hit by the ball and advances when Danielle Collins withdraws.

Iga Swiatek fell to her knees on the court and clutched her midsection after being hit by a ball during a women’s singles quarterfinal at the Paris Olympics on Wednesday, but it was her opponent, Danielle Collins of the United States, who stopped play later in the third set.

Swiatek was leading 6-2, 1-6, 4-1 when Collins retired from the match after taking a medical timeout and then getting another visit from a trainer.

Collins, 30, who was runner-up at the 2022 Australian Open and announced she would retire from elite tennis after this season, said she suffered a stomach muscle injury from cramping and dehydration due to a lack of cold water available during Tuesday’s match in temperatures that reached 97 degrees Fahrenheit.

She blamed Olympic organizers for not having insulated water bottles, for the water not being cold enough and for not “prioritizing the health of the athletes.”

“It’s incredibly disappointing because you work so hard your whole life to get to the Olympics – and this is my first and last Olympics – and something like not having enough water in the stadium, it’s really frustrating and really sad,” Collins said.

In the opening game of the final set, as Collins was serving for a draw, she sent a backhand into the middle of the court. Swiatek was standing at the net and couldn’t get out of the way of the shot.

Swiatek looked stunned as she dropped her white racket and came to a halt on the red clay of Court Suzanne Lenglen. Collins, who asked “Iga, are you okay?”, walked around the net to check on Swiatek, and umpire Damien Dumusois got up from his seat to see how the world number one was doing.

“I couldn’t breathe for a moment. It hurt a little bit. But with the adrenaline you feel on the court, you don’t feel strong enough,” Swiatek said.

Swiatek finally got up and nodded, indicating that she could continue.

Three points later, Collins hit a forehand long, and Swiatek broke her serve. She quickly broke again to take a 3-0 lead in that set, and Collins left the court for a medical break, delaying the match for about five minutes.

When they resumed play, the score quickly became 4-0 before Collins won the match, but then lost the match.

According to Collins, Swintek was scolded by Swintek when they spoke after the game, telling her, “She shouldn’t be dishonest about my injury.”

“There’s a lot that happens in front of the cameras. There are a lot of people who are incredibly charismatic… (who) come across one way on camera and another way in the locker room,” Collins said. “I don’t have to pretend.”

“I think I’d better ask her,” Sviatek replied when a reporter wanted to know the details of their post-match conversation.

In the semi-finals, Swiatek will face Cheng Chen Wen, who ended the great run of Germany’s Angelique Kerber in a thrilling match that ended with a score of 6-7 (4), 6-4, 7-6 (6).

Cheng failed to convert three consecutive match points in the third set as Kerber clung to the match in sweltering heat but eventually prevailed, falling to the red clay in disbelief as Kerber’s final shot hit the net.

Kerber, a three-time Grand Slam champion, announced last week that she would retire after the Olympics.

“I’ve achieved everything I’ve ever dreamed of,” Kerber said. “I was No. 1 in the world, I won Grand Slams, I won silver in Rio, so what more could you want in the end?”

Wimbledon champion Barbora Krejcikova of the Czech Republic was knocked out of the tournament after losing 6-4, 6-2 to Anna Karolina Schmiedlova. Schmiedlova has now eliminated the two women who played in the final at the All England Club two and a half weeks ago. Schmiedlova, who beat Wimbledon runner-up Jasmine Paolini in the third round on Tuesday, is the first Slovakian tennis player to reach the semi-finals at the Summer Olympics since 1988.

Krejcikova finished ninth in Paris and has had good results on the clay courts at Roland Garros, which hosts the French Open and is used for tennis at these Olympic Games. Her first Grand Slam singles title came at the 2021 French Open, when she also won the doubles title.

But with temperatures soaring to 90 degrees Fahrenheit and the air thick with humidity, Krejcikova looked helpless at the end of the match against Schmiedlova, the 29-year-old, world No. 67 who has reached the fourth round of a Grand Slam tournament only once, at Roland Garros last year.

By the end of the match, Krejcikova looked exhausted and barely moving. She hit a forehand into the net to end the match, and Schmiedlova raised her arms above her head.

The two players scored almost the same number of winning points, with Krejcikova scoring 18 points to Schmiedlova’s 17. The big difference was in unforced errors: Krejcikova had 32 points, more than double Schmiedlova’s 15 unforced errors.

This included five double faults by Krejcikova, who had to deal with 11 break points and lost five of her service games.

Schmiedlova will next play on Thursday against Croatian Donna Vekic, who erased a match point and needed five more to eventually beat Ukrainian Marta Kostyuk 6-4, 2-6, 7-6 (8) and the match ended after midnight.

The Associated Press and Reuters contributed to this report.