Venus Williams decided to back out of the U.S. Open to battle her recently discovered autoimmune disease.

Just moments before she was supposed to hit the court for her second-round match, Venus pulled out of the competition due to illness.

On "Good Morning America" today, Venus revealed that she's suffering from Sjogren's Syndrome, which can cause debilitating fatigue and joint pain.

"I think I've had issues with Sjogren's for a while. I just wasn't diagnosed," Venus said, explaining that her doctors likely hadn't caught the condition before now because it typically takes six-and-a-half years for the disease to be identified. "I was diagnosed this summer—a few weeks ago actually."

Venus said she's been struggling with a lack of energy for years, which she now believes was caused by her condition. The tennis pro said, however, that her symptoms were particularly bad this summer.

"For many, many  years, I always felt like no matter how much I trained, I never had enough stamina," Venus said, adding that she'd also been misdiagnosed as physicans tried to figure out what was wrong with her. "About four years ago, I felt like I wasn't getting enough air, and so I got diagnosed with exercise-enduced asthma, but my medicines never worked."

The athlete said she was alarmed when she started suffering other, more definitive Sjogren's symptoms such as joint pain. "My hands started swelling, my joints started to kind of change shape," she explained. "I had some of the classic symptoms: dry eyes and dry mouth."

Eventually the condition began to affect Venus' ability to play. "I lost a lot of feel—llke, I would miss shots by feet, and I just couldn't feel my hands. Or my hands would hurt when I was playing," she said.

Ultimately, Venus thinks there's a silver lining to experiencing the more serious symptoms of Sjogren's Syndrome. "I think the best thing that could have happened for me this summer was to feel worse so I could feel better," she said. "I feel like I can get better and move on."

Venus vowed that she won't allow her condition to take her out of the game forever, vowing that she will eventually return to the court.

Check out her full announcement below.
 

—Sonya Eskridge

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