The 36-year-old has not played since winning last year's tournament in Melbourne - when she was pregnant with her first child.
She has not played competitively since Melbourne, raising questions over whether the 23-time Slam victor would attempt to defend her title next month and equal Australian Margaret Court's singles record of 24 major titles.
Williams is now in the process of working towards a return for the 2018 season, with intentions to compete at Melbourne Park next month.
"She has got her visa, she has entered, she's practicing, and she probably just needs a bit more space for a bigger entourage", tournament head Craig Tiley said.
Margaret Court has the all-time record with 24. "It would be a pretty significant accomplishment for her to be able to do that".
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"It's the most outrageous plan", the American said. "I spent a lot of time at this center, just even out here on the courts with the kids".
"If I lose and I lose again, it's like, "she's done". Either I win, or I don't play".
Williams, who gave birth to a daughter in September, could return for the Australian Open next month.
Alexis Ohanian and Serena Williams attend the "Rei Kawakubo/Comme des Garcons: Art Of The In-Between" Costume Institute Gala at Metropolitan Museum of Art on May 1, 2017 in New York City.