Australia 153 for 7 (Healy 53, Kasperek 3-25) beat New Zealand 120 (Bates 48, Schutt 3-12) by 33 runs
Australia's toughest test of the tournament to-date only proved to further entrench their favouritism for the title.
Alyssa Healy continued her stunning form with the bat to help Australia cruise into the semi-finals. A third consecutive half-century and a sixth in eight T20Is underpinned Australia's strong but slightly underwhelming total given the platform set by Healy and her opening partner Beth Mooney.
But it proved too many for New Zealand, who without Suzie Bates' lone hand of 48 may have fallen short by far more than they did.
Both sides, however, may admit the margin was a little deceiving. New Zealand did expose some vulnerabilities in the powerful Australian line-up but failed to capitalise through some poor fielding. Amelia Kerr dropped Healy at point in the third over, letting a simple sliced sky ball slip through her fingers. Australia were just 16 runs from 16 balls at that stage.
But a bevy of boundaries from Healy intertwined with a stack of wides from New Zealand's bowlers saw the opening stand reach 71 in just 8.2 overs. It was the fourth consecutive 50-run opening stand between Healy and Mooney and the sixth in seven innings.
Australia's innings then stalled badly. Mooney holed out before Meg Lanning made a rare failure. Ash Gardner failed to rotate the strike adequately to leave Healy frustrated as she threw her wicket away on 53 from just 38 balls, bowled by Hannah Rowe stepping well outside her off stump trying to flick to leg.
Leigh Kasperek really put the brakes on Australia as skipper Amy Satterthwaite juggled her bowlers around with good effect. Kasperek removed the dangerous trio of Mooney, Gardner and Ellyse Perry in four overs that cost just 25.
But New Zealand dropped two more catches in the last two overs of the innings, crucially both off Rachael Haynes who ended up making an unbeaten 29 from 18 balls to tick the total past 150.
The chase got off to a horrendous start. Anna Peterson was trapped lbw by Megan Schutt in the first over and burnt New Zealand's sole review in the process. After Sophie Devine was clean bowled next over by Perry the review haunted New Zealand when Satterthwaite was adjudged lbw to Sophie Molineux in the third over attempting a reverse sweep. Replays showed she was struck outside the line.
It left New Zealand 13 for 3. Bates and Katie Martin mounted an excellent revival that put Australia under pressure. Bates got a reprieve when Healy dropped a sharp top edge off the bowling of Perry. The pair added 69 in 7.4 overs before Healy made amends with a silky stumping off the legspin of Georgia Wareham to remove Martin.
Bates keep finding the rope reducing the equation to a manageable 61 from 42 balls before Delissa Kimmince took two wickets in the 14th over to tip the game in Australia's favour, with Healy taking a stunning catch up the stumps to confirm her Player of the Match award.
Bates was correctly adjudged lbw by Gardner an over later despite skipping down the track to effectively end the chase and all-but end New Zealand's tournament with a second straight loss.