England's hopes of qualifying for the tri-series final have nosedived following a 12-run loss to New Zealand in Wellington.
A third successive defeat for the English, including two to Australia, means a trans-Tasman final will be assured if the Black Caps can beat Australia in Auckland on Friday.
The home side's 5-196 proved too steep at Westpac Stadium on Tuesday, with an English chase that went in fits and starts eventually ending at 9-184.
A blinding 47 off 24 balls from opener Alex Hales and 59 off 40 Dawid Malan gave England some hope but they didn't get sufficient support as the required run rate steadily climbed.
The wickets of Hales, James Vince - who was guilty of lazy running and was caught out by Kane Williamson's sharp throw - and stand-in captain Jos Buttler in quick succession through the middle stages proved crucial.
Spinner Mitchell Santner, rated the world's premier T20I bowler, took 2-29 off his four and had Malan caught in the deep in the 17th over to further tighten the noose.
Earlier, Martin Guptill and captain Williamson blazed half-centuries after New Zealand were inserted on a pitch that played truly despite its patchy appearance.
Opener Guptill raced to 65 off 40 balls and Williamson accelerated late in his 72 off 46 as both put some modest form by their standards by their lofty standards behind them.
Newcomers Mark Chapman (20) and Tim Seifert (14 not out) provided the late fireworks on their international debuts.
Buttler said England were too loose early on and the target was 10-15 runs more than acceptable.
"We were just off with our skills. We probably didn't bowl as well as we could have and Guptill and Williamson put us under a lot of pressure," he said.
Williamson was lucky not to be run out by Wood on the first ball he faced.
The skipper's spot has been under pressure after several ineffectual knocks in T20 internationals and his selection was called into question by former Black Cap Simon Doull.
Williamson responded with innings that began cautiously but later flowered with four fours and four sixes, defying a back niggle that had made him a doubtful starter.
He wasn't flustered during his post-match interview with Doull.
"You can write what you like, that's fine," Williamson said.
"Don't get me wrong, there's been a number of occasions recently where I've wanted to contribute more but it wasn't to be.
"It was nice to spend some time in the middle today to help our side get a good total."
England's hopes of contesting next week's final at Eden Park now rest on Australia winning the trans-Tasman affair at the same venue on Friday followed by England beating the Black Caps at Hamilton two days later.
Trans-Tasman T20 Tri-Series
First T20I Australia beat New Zealand by seven wickets. Scorecard
Second T20I Australia beat England by five wickets. Scorecard
Third T20I Australia beat England by seven wickets. Scorecard
Fourth T20I New Zealand beat England by 12 runs. Scorecard
Fifth T20I NZ v Australia, Eden Park, February 16
Sixth T20I NZ v England, Seddon Park, February 18
Final TBC, Eden Park, February 21
Australia squad: David Warner (c), Aaron Finch (vc), Ashton Agar, Alex Carey, Ben Dwarshuis, Travis Head, Chris Lynn, Glenn Maxwell, Kane Richardson, D'Arcy Short, Billy Stanlake, Marcus Stoinis, Andrew Tye, Adam Zampa.
England squad: Eoin Morgan (c), Sam Billings, Jos Buttler, Sam Curran, Tom Curran, Liam Dawson, Alex Hales, Chris Jordan, Dawid Malan, Liam Plunkett, Adil Rashid, Jason Roy, Ben Stokes, James Vince, David Willey, Mark Wood.
New Zealand squad: Kane Williamson (c), Tom Blundell, Trent Boult, Tom Bruce, Colin de Grandhomme, Martin Guptill, Anaru Kitchen, Colin Munro, Seth Rance, Mitchell Santner, Ish Sodhi, Tim Southee, Ross Taylor, Ben Wheeler.