Serena Williams has withdrawn from the women's doubles at Wimbledon Championships after a right knee injury ruled her out of the tournament.
The 44-year-old sustained the injury during her much-anticipated singles comeback earlier this week, when she lost 6-3, 6-7 (6), 6-3 to 20-year-old Australian Maya Joint.
Despite hopes she would recover in time for doubles, the injury forced her withdrawal before she and sister Venus Williams could take to the court.
Venus, 46, had already featured in the mixed doubles on Friday alongside Germany's Kevin Krawietz. The pair lost in straight sets to Tereza Mihalikova and Lloyd Glasspool.
The Williams sisters had been due to face Camila Osorio and Solana Sierra in the first round of the women's doubles.
Their match had been delayed to give Serena more time to recover, but she was ultimately unable to compete.
"I'm heartbroken to have to withdraw from doubles. Coming back to compete again has been a gift, and the opportunity to play alongside @venuswilliams once more meant the world to me. I did everything I could, but unfortunately my knee just isn't ready to compete," Serena wrote on Instagram.
The post included images of four syringes, which Serena said showed "the fluid they drained from my knee after my singles match". A video also showed the tennis great walking with heavy strapping on her right leg while one of her daughters carried a cane beside her.
Despite the setback, Serena suggested her return to competitive tennis may not be over, hinting at a possible appearance at the US Open.
"All I can say," she wrote, "is stay tuned to a city near you."
The withdrawal ends one of the biggest storylines of this year's Championships, with Serena and Venus set to reunite in Grand Slam doubles for the first time since the 2022 US Open.
The sisters are six-time Wimbledon women's doubles champions and have won 14 Grand Slam doubles titles together.
Serena's appearance at Wimbledon marked her return to singles competition after nearly four years away from the sport.
The 23-time Grand Slam singles champion accepted a wildcard into both the singles and doubles draws after returning to action in doubles events at Queen's Club Championships and the Berlin Open.
She stepped away from professional tennis after the 2022 US Open, saying she was "evolving" away from the sport rather than retiring.
Her comeback generated global excitement as she returned to the grass courts where she won seven Wimbledon singles titles.