One Kerr sister started the final T20I in Brisbane in style and another was there to finish it. Amelia Kerr will rightly take the headlines for her matchwinning all-round display of 2 for 18 and a nerveless 18 off 10 balls when New Zealand looking like messing up the chase, but Jess Kerr did what many cannot manage: bowl a maiden over to Alyssa Healy in the powerplay to open the match.

Medium-pacer Jess, who had not played the first two matches, did not end up with a wicket next to her name - she didn't even complete her four overs - but the string of dot balls she sent down to Healy was key in one of her less fluent innings as she departed for 8 off 14 balls, falling shortly after the end of the fielding restrictions in a period where New Zealand took a grip on the innings.

"It must be something in the Kerr family, nerves of steel," the visiting team's captain, Sophie Devine, said. "It was great for her - that's what you want from any player that comes into the team is to make an impact and she did it straightaway against one of the world's best batters.

"Huge credit to her. We thought she was a great match-up against both their [opening] batters, and to start a T20 match with a maiden is pretty incredible. It's credit to her and Jacob Oram, the bowling coach, in terms of honing those skills and when she does come into games she can have a great impact for us."

ALSO READ: Jacob Oram interview - 'Spin bowling one of the strongest skills in the women's game'

"The world is her oyster; I know she wants to bat up the order in time but the great thing is she's only 19 or something ridiculous, so she's got all the time in the world to figure out where she wants to be." Devine on Amelia

Then it was over to Amelia. As is so often the case for legspinners, it was a pair of her worst deliveries that earned her the wickets: a drag down that Rachael Haynes pulled to midwicket and a big full toss clubbed to mid-on by Meg Lanning. Her four overs included 10 dots and just one four.

However, for a period in New Zealand's chase when Katey Martin and Amy Satterthwaite fell in quick succession it looked like her work with the ball would go to waste. The equation blew out from less than a run-a-ball required to 25 off 18 deliveries, memories of the poor chase in the opening game still fresh in the mind.

This time, though, New Zealand held their nerve thanks to Amelia and some help from Hayley Jensen who struck a vital boundary off the last ball of the 18th over. Kerr then drove Sophie Molineux for a boundary before consecutive fours in the final over against Megan Schutt. There will likely come a time when she bats higher in the order, but despite being around international cricket for four years is still only 19.

"We all know how much talent Amelia has got; for us it's about nurturing her," Devine said. "She has a pretty calm head on her shoulders as we saw today and she's done it before, not only for New Zealand but also in the WBBL. The world is her oyster; I know she wants to bat up the order in time but the great thing is she's only 19 or something ridiculous, so she's got all the time in the world to figure out where she wants to be.

"There were nerves; not sure there was panic as such," Devine added about the closing stages. "We got ourselves into a really good position and from 10, 11 overs out we had the run rate under control. We saw in the first game, we probably blinked first so for us it was about keeping calm and taking it deep. We knew we had the batters and could get over the line."

A talking point from Australia's point of view was Lanning's decision to pull Georgia Wareham out of the attack after she had claimed the wicket of Martin and then not to use her final over on a worn surface. Instead she returned to the pace of Schutt with the New Zealand batters able to use her extra pace.

"I'd brought her [Georgia] on to get the wicket and the run rate got up to about eight and a half and I felt that was a good opportunity to bring Schutter, JJ [Jess Jonassen] and Soph [Molineux] back in to really try and close the game down which they have done really well for us over a long period of time," Lanning explained. "That was the thinking, getting that wicket then trying to squeeze as much as we could."

The teams will now prepare for the ODI series, where the Rose Bowl will be contested. It begins on Saturday. Australia have held the trophy since 1999.