Marsh is far from the finished product but he produced arguably his best performance in the international arena to save Australia's bacon in Wellington.

David Warner top-scored with a powerful 98 off 79 balls but Marsh was the hero. Just hours after being bought for $990,000 in the Indian Premier League player auction, the youngster belted a match-winning 69 to go with a handy 2-30 with the ball to see Australia home with 21 balls to spare.

The four-wicket win keeps Australia's streak of seven consecutive series victories intact but there are some danger signs leading into the deciding match of the Chappell-Hadlee series and, more importantly, the ensuing Tests.

What had been a comfortable run chase while Usman Khawaja and David Warner were dictating proceedings turned into a tense tussle after another middle-order stumble.

Again, it was the unheralded Matt Henry who delivered the goods for the Black Caps. Worryingly for Australia, he is causing plenty of headaches for Steve Smith. For the second time in as many games, Henry claimed the wicket of the Australian captain cheaply in an inspired burst.

Both times Smith has succumbed to well pitched up deliveries around the fourth stump line. At Eden Park he dragged one on to his stumps, this time he nicked off and was brilliantly pouched by Luke Ronchi.

A ball later, he comprehensively beat George Bailey with one that jagged back off the seam and crashed through his gate to hit the top of off.

The Kiwis were playing high-octane cricket, best illustrated by Adam Milne's stunning one-handed pluck to dismiss Matthew Wade. Wade was crestfallen and had good reason.

With James Faulkner sidelined, it seemed Australia did not have the lower-order batting power to pick off the remaining 85 runs.

But aided by an unbeaten 40 from the increasingly dependable John Hastings, Marsh finished off the Kiwis in a manner which Michael Hussey and Michael Bevan have done many times.

Precocious all-rounder: Marsh belted a match-winning 69 to go with a handy 2-30 with the ball to see Australia home with 21 balls to spare.

That he was able to see off Trent Boult under pressure will also do his confidence a world of good heading into the Tests.

Australia's unheralded attack set up the win with a disciplined performance on a track offering not much help to the bowlers.

Pace spearhead Josh Hazlewood had the pick of the figures with 3-61 from 10 overs but the key wickets were taken by the two most unlikely suspects - Zampa and Scott Boland.

Boland came onto the radar of national selectors on the intel from state coaches who felt a wicket was just around the corner when he had the ball in hand.

That has not exactly proven to be the case for Boland at international level. He had to wait 188 balls, four games and more than three weeks between his first and second wickets in the green and gold.

In his case, it was a case of good things come to those who wait, for he claimed the huge scalp of McCullum. Welcomed to the crease with a towering six by the Black Caps captain, Boland produced the perfect comeback the following ball, rattling McCullum's stumps as he tried to repeat the dose.

Zampa is known in state circles as being a feisty competitor with a healthy belief in his own ability. He needed every bit of that confidence.

Into his eighth over, Zampa had the uninspiring figures of 0-46. He had just been dispatched over the rope by Kane Williamson. Equally disconcerting was the risk-free nature in which the Black Caps were able to score at a run a ball of him.

Then out of nowhere Williamson picked out Steve Smith at extra cover and the next over he had Grant Elliott, the Black Caps' hero from last year's World Cup semi-final, caught in the same position by Glenn Maxwell.

Zampa's figures of 2-57 should ensure he gets a follow-up game. He is now also in strong contention to make Australia's World T20 squad.