Despite withdrawing from the U.S. Open because of an immune system disease, Venus Wiliams says she’s looking forward to a big comeback.

“Thank you everyone for all your well wishes! It’s good to have support!,” Williams tweeted. “Looking forward to getting better and back on tour!”

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The seven-time Grand Slam champ pulled out of the U.S. open after revealing she’s been diagnosed with Sjogren’s syndrome, a disease that causes fatigue and joint pain.

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She says she appreciates fans supporting her throughout the diagnosis. “Thank you 4 sharing all your sjogrens & auto immune stories w/me,” Williams tweeted. “Feels good to know I’m not alone! feel better to you and your loved ones!”