Australia are passing every test on the road to regaining the World Cup, continuing their dominance in New Zealand with a five-wicket win over South Africa to stay unbeaten.

The win over the Proteas was Australia's sixth in succession and they will finish their group stage campaign against Bangladesh on Friday.

In their six wins, Meg Lanning's side has won in all manner of ways.

They have won setting and they have won chasing.

They have won the toss and done it on their terms, they have lost it and responded to the challenge.

They have found match-winners among their pace attack and spinners, and each of the top five bats has posted a half-century.

At this point, it might be a better question to ask what is going to stop Australia, rather than whether they can do it.

"It certainly hasn't been easy," Meg Lanning insisted, fresh from 97 against India and 135 not out against South Africa.

"Teams come hard at us, they get up when they play against us and we're ready for that, to absorb a bit of pressure and then push back when we need to.

"It's been a very challenging tournament so far and we're expecting that to happen into the semi-finals as well."

Injuries and unavailability might be one cloud over Australia regaining the World Cup, ceded to England five years ago.

COVID-19 remains a spectre, with New Zealand continuing to record around 20,000 new cases a day during its worst outbreak of the pandemic.

And doubts now surround Ellyse Perry, who complained of back soreness and left the field after bowling three overs against South Africa.

Perry was not required to bat and will be put in cotton wool with bigger matches looming.

"We'll manage her over the next few days," Lanning said.

"Whether she's available for the next game, I'm not too sure but we need to have her for that semi-final and hopefully final.

There are questions too over Darcie Brown's durability given she was again rested for the South Africa match.

The South Australian teenager has taken three-wicket hauls in her two latest outings but was spared the hit-out against the Proteas.

"We look at every game as to whether she's physically in a position to play 100 per cent," Lanning said.

"Today was about managing her and hoping she's available for us every game back end of the tournament.

That leads to the other big question: whether Australia's attack packs enough punch.

It is an overly tough criticism given the side's unblemished record but Australia have only dismissed the other side twice, in routs over West Indies and New Zealand.

Ash Gardner, who has six wickets at an average of 21, admitted taking 44 wickets from the 60 available so far was not good enough.

"We're always striving to take 10 wickets," she said.

"One of our KPIs is to take 10 wickets … obviously, we haven't done that as well as we would have liked."

Both Gardner and Lanning said if they could not take wickets, the next best thing is keeping the run rate low.

"In one-day cricket, dots bring wickets," Gardner said.

"We have restricted [teams], which has created opportunities and sometimes we have  not taken those opportunities."

AAP