After scoring a comfortable 54-43 win over South Africa yesterday, the Proteas challenged the Ferns all the way.
The Ferns led by just one goal against the fifth world ranked side after the first quarter.
Sulu Fitzpatrick then replaced Kelly Jury at goal keep, in an attempt to tighten up the defensive end.
The Ferns led 28-25 at half time.
A plucky South Africa wouldn't go away - equalising with New Zealand midway through the third quarter.
They then took a three goal lead, while the New Zealand side started to look a bit shellshocked.
South African shooter Ine-Mari Venter was deadly accurate and a buzzer beater shot put the Proteas ahead by one going into the final 15 minutes.
The Silver Ferns were able to pick up more turnovers in the final quarter
Shooter Maia Wilson was crucial for the Silver Ferns - returning 39 from 44 at 89 percent.