Williams later posted a boomerang video of her cartwheel on Instagram with hitting partner Jarmere Jenkins in the foreground holding the trophy.
She captioned the post "Flipping to Melbourne. Thanks [Jenkins] #rockstarpartner," ahead of travelling across the ditch to compete in the Australian Open.
Minutes after her first tournament victory in three years Williams announced she was donating her prize money, $NZ65,000, to the Australian bushfires relief.
A dress worn by Williams at the Auckland tournament has a leading bid of $4,010 on TradeMe with around $20,000 already raised from successful auctions created by the tournament organisers.
The bespoke maroon Nike playing dress, signed by Williams, was worn by the tennis great during her battle with fellow American Christina McHale during last Thursday's match.
It comes with a letter of authenticity signed by Tournament Director Karl Budge.
Another auction for a Longines Saint-Imier Men's Watch sits at $3,000.
Proceeds direct from the Trade Me auctions for Best Seats in the House promotion, signed memorabilia and experiences total around $20,000 so far.
A one-hour training session with Williams' coach Patrick Mouratoglou sold for $1,551.
Bids for sideline seats will continue over the men's tournament this week.
"I've been playing in Australia for over 20 years and it's been really hard for me to watch all the news and everything that has been happening with all the fires," Williams said after her win in yesterday's final.
"Over a billion animals and people that have lost their homes. So much has happened, so I decided at the beginning of the tournament in every match I played I'd donate a dress and I'd also donate all my prizemoney for a great cause."
With Williams donating her prize money that took the donated total to $88,000.
More signed merchandise will be released on TradeMe from the likes of Genie Bouchard, and 2019 ASB Classic champion Julia Goerges.
ASB Classic are also donating $20 for every centre court ticket remaining sold to today's day session.