The Chappell-Hadlee Trophy will remain locked at Cricket Australia's Melbourne headquarters for another year after New Zealand were sunk by another dud batting effort in the fourth one-day international in Auckland today.

Australia won by 6 wickets with 17 balls to spare at Eden Park to take an irrefutable 3-1 series lead with the final match in Wellington on Saturday.

Aussies led by an unbeaten 50 from Cameron White and a blistering 50 off 35 balls from skipper Ricky Ponting were always on track after being set a rain-reduced Duckworth-Lewis target of 200 off 34 overs.

New Zealand opened the door wide for their visitors when they collapsed for 238 off 44.1 overs. Under the vagaries of the Duckworth-Lewis method, a 90-minute rain delay saw an original target of 239 off 50 overs somehow become 206 off 36. A further shower saw the target tweaked again to 200 off 34, leaving Australia requiring a challenging 5.88 per over and at least giving the hosts a sniff.

Earlier, it all seemed to be going to plan for New Zealand after their brains trust made the tough calls, axing Peter Ingram and Neil Broom and shuffling up their big guns into what appeared their ideal spots.

But from 120 for one, New Zealand collapsed to 238, criminally with 35 balls remaining.

Only a late flurry from Tuffey, who made 34 off 17 balls and clouted spinner Nathan Hauritz for three consecutive sixes, saved New Zealand from total embarrassment. A middle order collapse of five for 34 in 66 balls, including the big wickets of topscorer Brendon McCullum for 61, Ross Taylor for 15, Scott Styris for eight and Vettori for 12, stymied any hopes New Zealand had of posting a par total of about 300.