Prolific winger Portia Woodman and 18-year-old centre Sylvia Brunt both crossed twice as the five-times world champions ran in 10 tries in a bonus point win to delight the crowd at the Waitakere Stadium in the suburbs of Auckland.

Woodman's combination of power and pace was all but irresistible at times as she improved her tally to 18 tries in seven career World Cup matches and her overall mark to 36 in 22 tests.

Brunt scored the pick of the tries with her second effort, however, crossing in the 49th minute at the end of a sweeping 80-metre attack in which the ball passed through a series of New Zealand hands.

"I'm really proud of our mental strength," said New Zealand captain Ruahei Demant.

"I'm happy that we had the courage to play into space regardless of where we were on the field and didn't take the easy road by taking contact all the time."

With some dominant scrums and powerful rolling mauls, Wales gave New Zealand a reminder of potential challenges ahead if, as looks likely, they meet European powers England and France later in the tournament.

It was from the lineout drive, a major weapon for tournament favourites England, that the Welsh scored both of their tries through scrumhalf Ffion Lewis and number eight Sioned Harries.

Any hopes of a comeback after Lewis's try just before halftime were quickly extinguished, though, when Black Ferns lock Maiakawanakaulani Roos and centre Theresa Fitzpatrick crossed for tries in the four minutes after the restart.

New Zealand number eight Charmaine McMenamin was in the sin bin for the last 10 minutes but the New Zealanders still added further tries from flyhalf Demant and fullback Ruby Tui, the latter set up almost inevitably by another Woodman break.

"It was a brutal 80 minutes," said Wales skipper Siwan Lillicrap.

"I've got to credit the Black Ferns. When they throw the ball around, their pick-and goes, their offloads, their strength, they are brutal."

While New Zealand can afford to rest some of their players for their final pool match against winless Scotland, Wales now almost certainly need to beat Australia next week to reach the knockout rounds.

Meanwhile, Canada secured a spot in the women's World Cup quarter-finals with a 22-12 victory over Italy in an entertaining Pool B clash at Waitakere Stadium in the Auckland suburbs on Sunday, thanks to Emily Tuttosi who scored two tries.

Winger Paige Farries scored a superb early try to cancel out an even better solo effort from Italy's Vittoria Minuzzi, and Tuttosi crossed on the back of a rolling maul to give Canada a 12-5 half time lead.

Centre Sara Kaljuvee extended the lead with a try 10 minutes into the second half after the Canadian pack had stretched the Italian defence to breaking point, with Tuttosi scoring her second off the catch-and-drive soon afterwards.

Replacement Canadian lock Emma Taylor was sent to the sin bin for a late shot with 14 minutes remaining, but her short-handed team mates kept the Italians out until number eight Elisa Giordano crossed for a consolation try in the final minute.

"We came here wanting to win the World Cup and the first step is to get wins and bonus points, and we've managed to do that in our first two games against really tough opposition," said Canada skipper Sophie de Goede.

Italy, looking for a third successive win after beating France and the United States in their last two outings, played plenty of enterprising rugby but were unable to match the power of Canada in the tight and at the breakdown.

Fullback Minuzzi gave the best possible start with 32 seconds on the clock when she picked up the ball on the halfway line, ghosted past three defenders to reach the left wing and outpaced Farries to reach the line.

Farries replied in kind in the 18th minute, taking the ball at first receiver and cutting through the first line of defence with a show-and-go before rounding Minuzzi to touch down.

It was Canada's second Pool B win after their 41-5 victory over Japan last week and ensured they would reach the last eight whatever happens in their final opening-round match against the United States next weekend.

Italy could still join Canada in the quarter-finals.

"We need to win" next week, said Italy centre Michela Sillari. "So we need to focus on Japan and not think about this one."