The US Eagles won the inaugural World Cup in Wales in 1991 and reached the final of the next two editions but have lost five of their seven tests this year, including heavy defeats to both England and New Zealand, to drop to sixth in the world.
Third-ranked Canada look in better shape, having beaten their American neighbours 36-5 in the Pacific Four series in June and notching up victories over Australia, Italy and Wales this year.
Both teams will be confident of reaching the quarter-finals from Pool B, which also includes fifth-ranked Italy and Japan, the 13th-best team in the world.
The problem will come in the latter stages of the knockout rounds as England, New Zealand and France have looked a cut above the rest since women's test rugby resumed after the global health crisis.
Canada coach Kevin Rouet, however, said he had confidence that his side can bridge the gap and improve on their runners-up finish behind England in 2014. "We head to New Zealand with a desire and belief that we can compete for the Rugby World Cup trophy, the first in Canada's history," he said when announcing his squad.
Sophie de Goede, who will skipper the team from the back of the scrum, plays her first World Cup but has considerable rugby pedigree as the daughter of players who both captained Canada at global showpieces.
US coach Rob Cain has brought plenty of fresh faces into the Eagles programme since he took over in 2018 and only nine out of the 32 players in his squad took part in the last World Cup in 2017.
"We've got some exciting young talent (which) is really driving things alongside the more experienced players," the Englishman said last month.
"Lots of learning, lots of development these last couple of years, learning what the game looks like, understanding where we are, and learning how we can bridge the gap."
Prop Hope Rogers, who like many of the American players has moved to England in search of more playing opportunities in the Premier 15s league, will be appearing at her third World Cup after finishing sixth in 2014 and fourth in 2017.
With the United States hosting the World Cup in 2033, Rogers said she was looking to extend the legacy of teamwork and comradery to the younger players.
"It is about leaving the jersey better than you found it, so being able to pass it on to some of our young bucks (in their) first World Cup is just really exciting," she said.
"USA rugby is growing and I want those people coming after me to have that same feeling of wanting to work for it, wanting to make it better."
France relishing underdog status
Losing semi-finalists in seven of the eight women's Rugby World Cup tournaments, France are determined to break new ground in New Zealand and hope to deliver performances that do justice to the drive and ambition of the squad.
Two victories over world champions New Zealand last year showed what the French are capable of and veteran second row Safi N'Diaye (34) is counting down the minutes to their Pool C opener against South Africa on October 8th at Eden Park.
"We know what the French team is capable of in recent years. We managed to beat New Zealand for example, to beat South Africa too," she added.
"We are a great team. We have already beaten the best. If we don't have this ambition, we are not the French team.
"It's an ambition we must have and we know it will be difficult, we know that all teams prepare very hard," she added.
France enjoyed a 46-3 victory over South Africa the last time they met but N'Diaye said there was no danger of them taking any team for granted, especially after last month's 26-19 defeat by Italy.
That defeat had come shortly after France blanked the Italians 21-0 and N'Diaye said they would have carried more confidence into the World Cup with back-to-back victories.
"But at the same time, it allows us to work, to keep our feet on the ground and to realise that every team works and that there will be no easy matches.
"We are not pretentious. We know we're not going to go there as favourites, and we relish that." said N'Diaye.
"There are girls with experience in the group and girls who arrive with a lot of desire, with their youth and enthusiasm. And with this combination, we hope to go as far as possible."
One player light on experience but who could make a huge impact in New Zealand is Joanna Grisez (26), a surprise choice in coach Thomas Darracq's squad.
Grisez is uncapped in Union but has impressed in rugby sevens, helping France finish third at last month's World Cup where she scored three tries.
"She is an outstanding finisher," said Darracq.
"I've known her for years. She brings a lot of energy and she's also comfortable in the aerial game, which is an important element, given the evolution of the game."
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