They're the neighbours that might share a nod while putting out the rubbish once a week but won't be standing around the BBQ each summer.
It all started out so well. February 17, 2005 at Eden Park was the maiden international match in the 20-over format for both teams. The transtasman rivals played five times between 2005 and 2010, with Australia winning the first four matches followed by a remarkable tie and eliminator win for New Zealand at the now defunct AMI Stadium.
That was the last Twenty20 international, outside of tournament play, between the two sides. A match played in pre-earthquake Christchurch in which Steve Smith was a leg-spinner batting seven.
Join the Herald's live blog on the opening T20 from 9pm on Saturday
The most recent clash was in in Dharamsala at the 2016 World T20 where the Black Caps beat Australia by eight runs in a pool match.
Read more: Steve Smith keen to stay in charge despite dearth of ODI runs
This weekend's game will be just the third time the Black Caps will play a T20 clash on Australian soil. They played a one-off Twenty20 at the end of the 2008-09 tour, also at the SCG. Australia won a close match by just one run, but that was after Nathan McCullum hit a six off the last ball with the game out of reach.
It's also been a long time between celebratory drinks in coloured clothing for the Black Caps on Australian soil. New Zealand have never won a Twenty20 game in Australia and their last ODI victory was in 2009.
At the SCG the Black Caps have six wins in 22 ODIs, the last being in 2002.
Black Caps T20 matches against top tier opponents
Pakistan 18
South Africa 15
Sri Lanka 15
England 14
West Indies 13
India 8
Bangladesh 7
Australia 6
Zimbabwe 6
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