That loss prompted plenty of soul-searching in the New Zealand camp. Taumaunu spent hours poring over the video footage of their horror performance looking for answers.
They came in Thursday night's Quad Series finale, as the Silver Ferns produced their most complete performance of the year, winning 48-43.
Taumaunu said the win has restored her confidence that her side are heading in the right direction.
"I guess I have to say I'm reasonably relieved because we just have not looked like doing it throughout the Quad Series," said Taumaunu.
"One of the most satisfying things about [Thursday night] is that it showed progress. I thought there were some areas where we showed improvement during the Constellation Cup, but after that last game of the Constellation Cup and the one in Sydney, one had to question whether that progress was real.
"So to come out and do that against an Australian team that was in very good form, I'm pretty pleased about it."
While their midseason slump will largely be forgiven after the Ferns finished their season with a convincing win over Australia, the fact their lull coincided with a period of experimentation remains a concern.
There was marked drop-off between the first string side and the back-up combinations, which emphasised the work Taumaunu has ahead of her to develop new game plans that don't have such a heavy reliance on the "big three" - Casey Williams, Irene van Dyk and Laura Langman.
But Taumaunu was nevertheless confident the team had made some progress in this area.
She highlighted the development of Camilla Lees, who has gone from a fringe member of the squad to key midcourter and young talent Kayla Cullen, who has shown plenty of promise in her first few forays at centre. With Liana Leota and Joline Henry expected back next season after taking maternity leave this year, and injured midcourters Courtney Tairi and Grace Rasmussen nearing full fitness again, Taumaunu is comfortable with where her side sit at this point in the four-year programme.
"I think there is a little bit more depth there and we have a couple of players within the squad who are injured who I'm expecting to be back fully fit by the end of next year," she said.
"So I'm hoping those new ones that have developed their game this year have laid down a challenge to the incumbents who are wanting to come back and there will be more competition for places next year," Taumaunu said.
Silver Ferns season
Sep 16: New Zealand 54 Australia 52
Sep 20: New Zealand 50 Aust 49
Sep 23: Australia 59 New Zealand 53
Oct 14: New Zealand 63 S Africa 27
Oct 17: New Zealand 61 England 43
Oct 21: Australia 68 New Zealand 48
Oct 25: New Zealand 57 England 46
Oct 28: New Zealand 63 S Africa 24
Nov 1: New Zealand 48 Australia 43.
