Williamson, at No 3, laboured to eight off 21 balls that night. His T20 record as an opener is better than at No 3 — 38.51 (strike rate 121.03) in 27 innings vs 32.26 (120.43) in 47 overall.
But Guptill and Munro, aggressive and with good records, are locked in at the top, for now.
However move into the middle order. You have, in no particular order, Ross Taylor, uncapped wicketkeeper Tim Seifert, fellow debutant-in-waiting Mark Chapman, Colin de Grandhomme, Anaru Kitchen and Mitchell Santner.
All could be in the XI to play England in Wellington next Tuesday, along with new ball pair Tim Southee and Trent Boult and legspinner Ish Sodhi.
That blend would leave left armer Ben Wheeler out and....someone else. So there is some hard thinking for selectors Gavin Larsen and coach Mike Hesson.
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In that middle order mix, who bats where? Or do you have six players padded up to be called in at any momenbt depending on the innings situation?
You wouldn't do it in a test or ODI but T20 is short, snappy and it might be one remedy.
That requires nimble thinking and players are often peculiar beasts in that they like to know where they are batting. Many don't like being unsettled in that way.
The veteran Taylor averages 40 at a strike rate of 122 when batting at No 5.
He smeared 22 not out off 13 balls in Wellington last month against Pakistan at No 5, and his 25 off 11 balls against the same opponents a few days later at Mount Maunganui in that series decider was at No 6, a fast, violent assault in a lost cause.
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His 24 off 35 in Sydney came when he had walked in at 16 for three.
So there's a case to put him down one spot, or possibly to No 6, and promote a hitter, perhaps a Seifert or de Grandhomme. Or both.
After that it's anyone's guess. The two new men, if both play in Wellington, are likely higher than lower in the order.
Santner would be the lowest of this group and de Grandhomme simply can't be wasted down at No 7 again, after his hitting in Sydney in New Zealand's wretched performance last weekend when he was the one shining light.
You suspect there's no right and wrong solution, no simple figuring out the right order, so the selectors, and presumably Williamson need to back their hunches.
One of Kitchen, or possibly Chapman, may sit out Wellington. Probably Kitchen. Better to get the new man in sooner rather than wait.
Whatever. New Zealand need to find a way to stop the losing streak at three. If not, their chances of being in the final at Eden Park on February 21 would correspondingly take a bit hit.