The tennis great posted the news on her Instagram feed Wednesday morning.
"After careful consideration and following the advice of my doctors and medical team, I have decided to withdraw from the US Open to allow my body to heal completely from a torn hamstring. New York is one of the most exciting cities in the world and one of my favorite places to play - I'll miss seeing the fans but will be cheering everyone on from afar. Thank you for your continued support and love. I'll see you soon."
Williams has not competed at any tournament since retiring from her first-round match at Wimbledon after injuring her right leg on June 29.
The 2021 US Open is set to take place August 30 - September 12 at full capacity in New York City.
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