Serena Williams reveals gruesome photos of injury as she's forced to pull out of Wimbledon

Tennis fans had been counting down the hours to one of the most emotional reunions of the tournament, but now it's not going to happen.

Serena Williams and her sister Venus were due to team up for a doubles match at Wimbledon this weekend, a full ten years on from the last time the pair lifted the women's doubles title together at the All England Club.

It would have marked their 15th major Championship as a pairing, and with the match falling on July 4, a federal holiday back home in the United States, the symbolism wasn't lost on anyone following the tournament.

Why has Serena Williams pulled out of Wimbledon?

Serena, 44, has now confirmed she's withdrawing from the doubles competition entirely, just hours before she and Venus were due to walk out on court together.

The American tennis icon picked up a knee injury during her singles defeat to Australian rising star Maya Joint on Centre Court, with Williams reportedly needing medical attention behind the scenes after appearing to "tweak" the joint mid-match.

She'd been scheduled to practise at Aorangi Park over the weekend but hadn't been spotted on site for several days beforehand, leaving fans and organisers unsure whether she'd be fit in time.

What happened to Serena Williams' knee?

Taking to social media, Williams shared a video of herself hobbling around her rented Wimbledon accommodation with heavy strapping wrapped around her right knee.

She followed it up with a gallery of pictures showing fluid being drained from the joint, footage that left plenty of her followers wincing at their screens.

Alongside the post, she wrote, "I'm heartbroken to have to withdraw from doubles."

"Coming back to compete again has been a gift, and the opportunity to play alongside Venus Williams once more meant the world to me."

She continued, "I did everything I could but unfortunately my knee just isn't ready to compete."

The announcement puts an end to what would have been a genuinely rare sighting of the sisters competing together, with Serena having stepped away from the sport in recent years and only returning to competitive tennis relatively recently.

Given her age and the injury concerns now surfacing, there's no guarantee the pair will get another shot at a Wimbledon doubles run together, making this withdrawal all the more bittersweet for fans who'd been building up to the moment for weeks.