Australia's world number one Ashleigh Barty and defending champion Naomi Osaka are among her genuine challengers, but pressure and expectation will also pose problems for Williams as she pursues the 24 Grand Slam titles won by the Australian Margaret Court between 1960 and 1973.
"That was really important for me and I just want to build on it," Williams, now ranked ninth in the world, said after triumphing in Auckland on Sunday. The former number one, who celebrated on court with daughter Olympia, donated her US$43,000 winner's cheque to victims of the Australian bushfires.
Practice and qualifying have been disrupted in Melbourne this week because of toxic air pollution from the deadly fires, but organisers are confident the tournament will proceed as planned. Williams has now won 73 WTA titles over four decades and although she is scaling back the number of tournaments she plays, there is no indication she plans to retire imminently.
Williams's latest Grand Slam final heartbreak came at the US Open, where she was stunned by Canadian teenager Bianca Andreescu. Williams - the highest-paid female athlete in the world last year with earnings close to US$30 million, according to Forbes - afterwards played down her bid for Court's record.
"I'm not necessarily chasing a record," she said. "I'm just trying to win Grand Slams." At least she will not encounter the 19-year-old Andreescu, who is out of the Australian Open with a knee injury. Of the challengers to Williams, Barty will also have to deal with great expectations from the Melbourne crowd.
The 23-year-old Australian, who once took time off tennis to play professional cricket, won her maiden Major at Roland Garros last year. But Barty has had a patchy start to the year after losing her season opener last week, going down in two sets in Brisbane to American qualifier Jennifer Brady.
She dismissed afterwards the hype in Australia surrounding her. "It doesn't change the way that I practise, it doesn't change the way that my team and I prepare, it doesn't change me as a person," Barty said.