"I love it here," Venus said after the 2015 ASB Classic. "Tennis feels different here than most places. Tennis can be very stressful but when you come here, you feel all the more at ease. I waited until I was 33 to come to New Zealand and that was one of the biggest mistakes of my life."
Venus has talked several times of trying to persuade her sister to make the trip and that message may have got through.
"Again, [Venus] said this year, 'They really want you there, you should go'," said Serena.
"I usually listen to big sis [and] she's a big influence, obviously."
Securing Serena would be a massive coup for New Zealand tennis. Williams had won 18 grand slam singles titles before last night, behind only Margaret Court (24) and Steffi Graf (22), and is regarded as one of the greatest females to wield a racquet. Like her sister, her appeal goes way beyond tennis, and even sport, and she gets recognition from Beijing to Bogota.
"It would be huge," said ASB Classic tournament director Karl Budge. "In my view, Serena is the best female player in the history of the game. She's been a champion for so long, across all surfaces. She'd be the biggest sports star we've had here for a long time. We'll do everything possible to make it happen."
Despite Serena's encouraging words, there would be many hurdles to clear. Budge started that process last week with an extended meeting in Melbourne with Serena's management team which he described as "very positive".
It's also a plus Williams is open to varying her early-season schedule. In 2009 and 2010, she started her season in Sydney before three appearances (2012-14) in Brisbane. This year, she played Hopman Cup.
Williams will carry a significant investment. Maria Sharapova is the previous biggest marquee female to play here but Williams goes beyond that, expected to command a significant six-figure sum as an appearance fee.
"We need to get the right commercial model in place but with players like Serena, and a lot of the top girls, I don't think it's all about the money," Budge said. "It's about a concept that can make it work for all parties. It's about making Serena want to come here."
One impediment is the WTA rule which allows a US$250,000 ($343,318) tournament such as Auckland to have only one top 10- ranked player in their field. Over the next 12 months, Venus Williams could remain outside the top 10 but other potential targets such as Caroline Wozniacki and Ana Ivanovic are likely to be inside that elite group.
"It's challenging for us," Budge said. "The best thing is to lock things in early so we know where we stand."