South Africa are in complete control of the second Test after New Zealand were left reeling at 6-47 at stumps on day two in Port Elizabeth.
Following the Proteas' first innings declaration at 8-525, New Zealand stumbled to Saturday's close of play still 478 runs in arrears after paceman Dale Steyn (2-14) wreaked havoc with the crucial wickets of Martin Guptill and Kane Williamson.
Wicketkeeper BJ Watling (15) and Doug Bracewell (three) remain at the crease.
After producing a disappointing performance with the bat in the opening Test in Cape Town, New Zealand's batsman were determined to put things right in Port Elizabeth.
But their attempts took a hit in just the second over when opener Guptill edged Steyn's delivery to Alviro Peterson for one, taking his combined tally in South Africa to a woeful two runs in three innings.
The Black Caps' problems were compounded two overs later when Kane Williamson (four) became Steyn's second victim.
Dean Brownlie (10) and Daniel Flynn (0) were the next to depart off the bowling of Rory Kleinveldt, who ended the day with figures of 2-18.
Captain Brendon McCullum (13) tried to stymie the South African pace attack but he was sent to the pavilion by Robin Peterson, who claimed the scalp of Colin Munro next ball.
Earlier, Faf du Plessis and Dean Elgar starred with the bat as the Proteas asserted their dominance.
Du Plessis hit 137 runs, his second Test century, while Elgar finished unbeaten on 103.
The home side began the day on 4-325 and only lost the wicket of opening-day hero Hashim Amla in the morning session for 110 off the bowling of Trent Boult (1-108).
Du Plessis showed plenty of patience in his quest for a second Test century before reaching the mark with a six after lunch.
Munro (2-40) eventually claimed his prized wicket and added Peterson (eight) shortly after with South Africa on 7-481. Doug Bracewell finished with three wickets.
Elgar was nine runs shy of a Test century as an impending declaration approached but skipper Graeme Smith allowed the 25-year-old to bring up his 100.
The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of Cricket Australia
First Posted 13 January, 2013 8:47AM AEST