Five run-outs were the undoing of South Africa, which saw them go down by 27 runs to New Zealand in the second one-day international in Kimberley on Tuesday night.
The Proteas also conceded the three-match series 2-0, with one to play in Potchefstroom on Friday.
Set a target of 280, the Proteas were cruising at 135 for one.
Graeme Smith and Colin Ingram had added a 129 runs off 135-balls for the second wicket but the problems started when Smith was run out for 66 attempting the third run.
Ingram would go on to make 79 off 94 balls.
The Proteas would go on to lose their last five wickets for 41 runs.
Earlier, Kane Williamson’s 145 not-out helped New Zealand post 279/8 as he went on to achieve the highest individual score by a Kiwi against South Africa.
