The impressive Martin Guptill set up the Black Caps winning total after they had won the toss with his innings of 60 (35 balls, 6 fours and 3 sixes) and, in partnership with his captain, Kane Williamson, again enabled his side to score more than 50 in the six Powerade powerplay overs.
This time they managed to kick on during the back end of their innings and scored a further 59 in the final 6 overs.
Not surprisingly, Guptill was named both KFC Man of the Match and of the Series with his aggregate of 102 runs from 72 balls.
The Proteas lost too many wickets up front in their reply and paid the price for not being able to put any substantial partnerships together. The pick of their line-up was Farhaan Behardien who showed good judgment in rotating the strike and hitting boundaries on his way to his career best score in this format of 36 (27 balls, 3 fours and a six).
The Proteas went into the last six overs needing 75 runs but did not come close to this target as they also lost a wicket in each of the first four overs of this phase. It meant that David Miller, the last power hitter, was left without the support he needed to take up the challenge.
Mitchell McClenaghan and the two spinners, Nathan McCallum and Ish Sodhi, took two wickets apiece.
With Morne Morkel missing out through paternity leave the Proteas were able to play two specialist spinners in Aaron Phangiso and Eddie Leie in their only change from the first match.
The format now changes to the 50 overs version with the first Momentum ODI taking place at SuperSport Park on Wednesday. Spectators are reminded that the starting time is earlier than normal at 12h30.