The 23-time Grand Slam champion took to the field with her daughter Olympia, who turns three in September, as the pair sported matching purple outfits.
In photos posted on Williams’ Instagram, the pair are seen celebrating, sharing a high five and stepping off the court – where Olympia leaves her racquet with her mom.
The coronavirus outbreak means Williams has not played since the Fed Cup playoffs in February in Washington.
The WTA Tour is set to return in August before the US Open later this month, although Williams coach Patrick Mouratoglou recently told CNN he doubts she will play in New York if her family and her girl couldn’t be there with her.
Williams subsequently made a video announcement letting fans know she would be playing at the US Open.
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Strict measures have been proposed by the American Tennis Association to allow the grand slam to take place, including the proposal to create a bubble for players at an airport hotel outside of Manhattan – where most players stay – and limit the number of entourage to one.
Williams, 38, has been open about motherhood lawsuits since her daughter was born in 2017.
She recalled the “deadly” experience of childbirth and her struggle with postpartum emotions when she suffered the heaviest loss of her career.
After her loss in the Wimbledon 2018 final, Williams said she was playing for “all moms”.
Another Grand Slam victory, the last of which she won the 2017 Australian Open, would see Williams tied with Margaret Court’s record.