An outstanding unbeaten 145 from Kane Williamson and some superb fielding set up the Black Caps for a dazzling 27-run win over South Africa in the second one-day international in Kimberley.
After their one-wicket victory in the opening game of the three-match series in Paarl, the win marks the first time New Zealand have won a series in any form of the game in South Africa.
· BlackCaps batting highlights
· Black Caps fielding highlights
On a benign batting track, the Black Caps set a competitive 8-279 after world No.1 South Africa won the toss.
The early dismissals of opener Martin Guptill and BJ Watling left ninth-ranked New Zealand teetering at 2-32 midway through the 13th over.
But Williamson and Grant Elliott put on 127 for the third wicket, setting a solid foundation for Williamson to bat out the innings.
His 145 was his third one-day century, the highest by a New Zealander against South Africa, and played a pivotal role as the Black Caps set their highest one-day total against the Proteas.
Williamson displayed excellent timing and placement in his 136-ball innings, which included 17 fours and one six.
In reply, South Africa looked in total control, losing only opener Quinton de Kock to be cruising at 1-167 early in the 31st over.
But once Graeme Smith was run out for 66 by a pinpoint James Franklin throw from the boundary, the Proteas lost wickets regularly and were left needing an unlikely 28 off the final over with just one wicket in hand.
Otago all-rounder Jimmy Neesham ended things, bowling Lonwabo Tsotsobe with the first ball of the over.
All out for 252, the Proteas were undone by New Zealand's brilliant effort in the field, with five wickets coming from run outs - equalling the record for an ODI, and they narrowly missed out on a sixth.
Captain Brendon McCullum said afterwards that the win was immensely satisfying after New Zealand lost both Tests by huge margins earlier this month.
"I'm not going to underplay it - it's a phenomenal effort," he said.
"To be 2-0 up in the series is incredibly satisfying, and it'll probably go down as one of our biggest-ever wins in the limited overs game.
He said Williamson's contribution was superb.
"I thought Kane's innings was as good an innings as I've seen from a New Zealander in one-day cricket. A few guys backed him up as well, and the way we were in the field was outstanding."
The third one-day international is scheduled for Saturday (NZT) in Potchefstroom.
New Zealand 279-8 in 50 overs (Kane Williamson 145 not out, Grant Elliott 48; Morne Morkel 3-71), South Africa 252 all out in 49.1 overs (Colin Ingram 79, Graeme Smith 66; Kyle Mills 2-28).