Rennae Stubbs coaches Serena Williams during practice in preparation for the 2022 US Open on Monday. AFP
After announcing earlier this month that the countdown to her retirement had begun, Williams will step on court at Arthur Ashe Stadium at Flushing Meadows for what could be her final appearance in a Grand Slam singles event.
The 40-year-old sporting and cultural icon won the first of her Grand Slam titles at the same venue in 1999, lifting the trophy as a fresh-faced 17-year-old.
In Monday's sold-out night session, which starts at 7pm (2300 GMT), Williams will face Montenegro's Danka Kovinic, the world number 80.
Whether Williams is able to extend her US Open campaign beyond that match remains to be seen.
In her last outing at the Cincinnati Masters earlier this month, Williams was thumped 6-4, 6-0 by Britain's Emma Raducanu -- who herself was knocked out of the Australian Open by Kovinic in January.
Win or lose on Monday, Williams won't be departing the US Open stage immediately.
On Saturday, organisers confirmed that she and elder sister Venus Williams had been given a wild card into the women's doubles tournament, which starts on Wednesday.
It is the first time the Williams sisters have played doubles since 2018, reuniting a partnership that has yielded 14 Grand Slam titles and three Olympic gold medals.
Whenever Serena Williams does leave the stage, she will do so after a career that has left a lasting legacy on her sport.
"I just think she's the biggest thing that will ever be in the sport," said Japan's Naomi Osaka on Saturday.
"It's just really an honour just to watch her play. She's giving us a chance to watch her more."