England beat Australia as WXV1 women's rugby tournament debuts
Australia finished with 14 players after lock Annabelle Codey was sent off for a second yellow card.
England's forwards dominated throughout with fly-half Holly Aitchison controlling the game and landing all six conversions.
"It was a good performance and a good starting block for us in the tournament," said Packer.
"We talked about going out there being courageous and I definitely think we did that."
The match in Wellington launched WXV1 - a new tournament for the world's top six teams.
New Zealand, Australia and Canada from the Pacific Four competition will each play Six Nations teams England, France and Wales.
Wales take on Canada and hosts New Zealand play France in Saturday's double-header, also in Wellington.
The third and final round of matches will be in Auckland, where New Zealand play England, the world's top-ranked team, in a repeat of last year's World Cup final won by the Black Ferns.
Packer carried on where she left off last April in the Six Nations, when she top-scored with seven tries and England won a fifth straight title.
"I have a good pack in front of me and I'm just the lucky one who comes up with the ball," Packer said of her two tries in Wellington after her pack drove her over the line.
The Red Roses made a flying start when prop Hannah Botterman barged over for a try after five minutes.
Winger Jess Breach then put scrum-half Ella Wyrwas over before claiming one of her own after Packer had also crossed for her first try.
Australia fought back, with centre Georgina Friedrichs carving through the England defence.
But ill-discipline cost the Wallaroos, Packer and Breach both touching down England tries when Codey was yellow carded for a shoulder-on-head contact.
England led 28-0 at the break and stayed on top when Packer touched down again early in the second half.
Australia grabbed a consolation try when replacement prop Ashley Marsters barged over from a quick-tap penalty.
It was business as usual from the kick-off when England won a turnover and centre Megan Jones darted over for their sixth converted try.
Codey was sent off for a high tackle in the build-up, but Australia's defence held out for the final 23 minutes.
"Staying in the fight was a positive," said Australia head coach Jay Tregonning as his side restricted England to two tries in the second half, "but it was our execution which let us down".
England play Canada next Friday in Dunedin, where Australia take on France and New Zealand host France the following day.
