Serena Williams retired from her first-round match at Wimbledon on Tuesday against Aliaksandra Sasnovich with a left leg injury.

Holding a 3-1 lead in the first set, Williams slipped and needed to take an injury timeout at the game's conclusion to receive treatment. She returned to the court, but her movement was visibly limited.

Williams was serving in the fifth game at Centre Court when she lost her footing near the baseline while hitting a forehand. She winced and stepped gingerly between points, clearly troubled.

After dropping that game, she took a medical timeout and tried to continue playing. A crying Williams bit her upper lip and covered her face between points. The crowd tried to offer support and encouragement. But eventually, the 39-year-old American dropped to her knees, and the chair umpire came over to check on her.

The match ended at 3-all in the first set.

Williams, a seven-time Wimbledon singles champion, gave an emotional wave to the crowd and held her hand over her heart as she fought back tears before she exited the court.

"Of course I'm so sad for Serena; she's a great champion," Sasnovich said. "It happens sometimes in tennis, but all the best for her and her recovery."

This marks just the second time in Williams' storied career she has retired from a match at a major. The other occurrence was in the third round at the All England Club in 1998.

Williams entered the tournament in search of her 24th major title, which would have tied her with Margaret Court for the most ever. She last won a Grand Slam at the Australian Open in 2017 and has made four finals since returning after giving birth, including at Wimbledon in 2018 and 2019. She made the semifinals at the Australian Open earlier this year as well as the fourth round at the French Open last month.

Her departure makes a wide-open women's draw even more so. As it was, defending champion Simona Halep and four-time major champ Naomi Osaka withdrew before the tournament started.

"Yeah, it was not easy to watch," said Coco Gauff. "Actually I turned away. I was in the gym actually stretching. I turned away because stuff like that makes me, like, really emotional.

"I mean, I wish (Serena) the best. I wish that hopefully she can have a speedy recovery. Yeah, you could tell she was really emotional. Nobody ever wants to retire, but especially at a Grand Slam, a place as special as Wimbledon after waiting two years to come back. The only thing I can do is wish her well wishes and hope she'll be back in time for the hard court season."

Williams was the second player on Centre Court on Tuesday to slip and suffer an injury. Adrian Mannarino, who was playing against Roger Federer, also was forced to retire as a result of a similar fall. Due to rain, the roof had been closed.

"I do feel it feels a tad more slippery maybe under the roof," Federer said after his match. "I don't know if it's just a gut feeling. You do have to move very, very carefully out there. If you push too hard in the wrong moments, you do go down. ...

"This is obviously terrible that it's back-to-back matches and it hits Serena as well. Oh, my God, I can't believe it."

Top-seeded men's player Novak Djokovic fell twice in the first set of his first-round victory Monday in the main stadium, too.

Information from The Associated Press was used in this report.