From halfway through their chase for 178, South Africa were behind the pace and New Zealand's 32-run win sets up the three-game ODI series nicely.
New Zealand might have felt they had more than 177 for seven in them, having won the toss, after man of the match - and series - Martin Guptill and captain Kane Williamson rattled on 52 in 5.3 overs.
Guptill went on to 60 in 35 balls, but was left to bemoan the fact he hadn't kicked on to closer to three figures.
There were handy cameos from Grant Elliott, Jimmy Neesham and Colin Munro, all of whom rattled along at better than a run-a-ball rate.
For South Africa, the game was a new experience. Never before has an international been played at Centurion in August. The pitch kept lower than might have been anticipated and New Zealand were on the job.
Hashim Amla and captain AB de Villiers were gone before the end of the seventh over and when Mitchell McClenaghan got his second wicket, removing the dangerous David Miller, the game was up for the hosts.
"The guys did a fantastic job with the ball and were great in the field," Guptill said. "Today was a much more complete performance than the other night and we got rewards for it."
The clock is ticking on the world T20 tournament, to be hosted by India from March 11.
New Zealand have five T20 internationals against Sri Lanka and Pakistan to come in their home summer to fine-tune their preparations.
For players such as Munro, Adam Milne, Ish Sodhi and George Worker, who has made a good fist of his two T20s against Zimbabwe and South Africa - 62 off 38 balls in Harare, and 28 off 26 in Durban - it's an important time to make a statement about the parts they can play in India.
So while there might be a temptation to mutter darkly about them being only a couple of T20s, there was more riding on them than that.
Three ODIs remain, starting at Centurion tomorrow night. New Zealand won their last clash. You might remember it. Eden Park. March 24. World Cup semifinal.
As things stand, you won't see a ball of this rubber.
A shame.