After days of rumors and speculations, Serena Williams has withdrawn from the doubles draw at Wimbledon. This means that her sister Venus Williams will also have to pull out, which will see the duo of Solana Sierra and Camila Osorio advance into the second round. Serena shared a worrisome injury update as she announced her withdrawal from the event.

“I’m heartbroken to have to withdraw from doubles,” she wrote in an Instagram post. “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 to be ready, but unfortunately my knee just isn’t ready to compete.”

It had previously been revealed that Serena had sustained a knee injury during her singles clash against Maya Joint earlier this week. Though the 44-year-old had a handful of days to recover from the issue, she eventually couldn’t do so.

Many fans had suspected the seriousness of the injury at first as Serena didn’t appear to be in discomfort during the match. But she has herself has now showed that the injury wasn’t made up. She can be seen wearing bandaging on her left knee in one of the pictures that she shared. She also shared a picture of four syringes that were used to drain fluid out of her knee after the match against Joint.

“The photo of the syringes shows the fluid they drained from my knee after my singles match…yikes! The good news is my knee shouldn’t swell or collect that much fluid again. The bad news is that, as hard as I tried, I just wasn’t able to get it ready for doubles,” she concluded.