An unbeaten 67-run partnership from openers Tom Latham and Jeet Raval gave New Zealand the edge after a rain interrupted Day 2.
Earlier, wicketkeeper-batsman Quinton de Kock made an invaluable 90 to rescue South Africa from 190-6 to take them to 314.
New Zealand 67 for 0 (Latham 42*) trail South Africa 314 (de Kock 90, du Plessis, 53, Amla 50, Henry 4-93) by 247 runs.
Matches Tagged in ClipDex2017 NZL v RSA 3rd Test
Series Tagged in ClipDex2017 NZL v RSA Test serie ...
Players Tagged in ClipDexde Kock, Quinton Raval, Jeet Ashok Rabada, Kagiso Latham, Thomas W M Du Plessis, Faf Henry, Matthew James
Grounds Tagged in ClipDexSeddon Park
Categories Tagged in ClipDexTest Matches