The 40-year-old had previously announced that this year’s tournament would be her last and, after a stuttering, error-strewn start, she made her way into the second round in New York with relative ease in beating Danka Kovinic 6-3, 6-3.
It means her second-round match late into the New York night on Wednesday will take place 24 years to the day since making her US Open debut.
After fairly limp early losses at her previous two tournaments, this first-round match felt every bit the farewell.
She was greeted on court by a video narrated by Queen Latifah, her every move cheered by the likes of Bill Clinton, Mike Tyson, Anna Wintour and Lindsey Vonn.
Williams didn’t produce the vintage tennis of her pomp when she won 23 Grand Slam titles as she produced five double faults in the opening set. But then again she didn’t need to against an opponent, who was clearly daunted by the enormity of the occasion and managed six double faults of her own in that opening set.
Following the win, Williams said: “When I walked out, the reception was really overwhelming. It was loud and I could feel it in my chest. It was a really good feeling. It’s a feeling I’ll never forget. That meant a lot to me.
“The crowd was crazy. They really helped me pull through. I was really pumped up, like, ‘Yes, I got this’.”
Her every shot was greeted as though the stage and the level of the match was infinitely higher rather than merely the first round of a Grand Slam.
She faces a tough ask to stay in the tournament and qualify for the third round against No2 seed Anett Kontaveit.
But the American, who had lost last week against Emma Raducanu in Cincinnati, said: “At this point, everything is a bonus for me. I think every opponent is very difficult. I’ve seen that over the summer. The next one is even more difficult.
“It’s good that I was able to get this win under my belt. I’m just not even thinking about that [her next match]. I’m just thinking about this moment. I think it’s just good for me to live in the moment now.
“It’s so important to give your all no matter what you do, how many obstacles you face. I’ve been down so much so many times in the public eye, and I’ve had to come back. But never give up. No matter what you’re going through, I just want people to be inspired by my story. I’m from Compton, California, and I made it.”