At 137 for two at stumps, New Zealand will still entertain hopes of victory if Brendon McCullum (58) and Ross Taylor (48) remain at the crease well into today's second session. Their third wicket partnership has been worth 82. Both applied themselves in getting behind the ball. In contrast, Martin Guptill and Rob Nicol found the going tough, illustrating the chasm between the Zimbabwe and South African attacks.
On a placid wicket, albeit with variable bounce (judging by the number of balls Kruger van Wyk snatched from his bootlaces), South Africa's batsmen tested New Zealand's tenacity.
Jacques Rudolph dominated the fourth day, raising his sixth test century as he added to the base built by Smith and Jacques Kallis. It was his first century batting at six having returned to the side in November after more than five years.
The 30-year-old punished New Zealand between third man and cover where he hit 11 of his 15 boundaries. He was also strong off his pads with 16 singles on the leg side.
Daniel Vettori gave him the best test of the New Zealand bowlers but Rudolph was rarely under threat; he was regularly prepared to sweep with the spin.
The New Zealand pace attack struggled to penetrate a batting line-up which found measure and control on a wicket that had lost its bite. The brief joy of removing Kallis early in the day for 113 evaporated quickly as AB de Villiers strode out. He was dismissed for 29 swiping to deep midwicket but it illustrated the difficulty New Zealand will have taking 20 wickets in either of the next two tests.
Doug Bracewell looked the most attacking of the New Zealand quicks, highlighted by his three wickets for 70. Those figures could have included a fourth had Rudolph not opted for a referral when given out lbw for 12 yesterday.
Chris Martin and Trent Boult had their moments; Martin was persistent and Boult provided useful left-arm variation. However, Tim Southee looks to be struggling. It may be a hangover from the one-day series as he adapts back to fuller lengths.
In the first innings, he had figures of none for 40 off 10 overs; 35 of those runs were square of the wicket. He also went wicketless in the second innings with 78 of the 100 runs conceded square.
New Zealand might opt to use Tarun Nethula on what could be a drier, more spin-friendly surface late in the Hamilton test.
In addition to enduring the prolonged use of South African bats, the weather also sapped New Zealand's energy. A blustery nor'easter meant full-length sweaters, with some of the slip cordon also opting for what looked like mini heated wheat bags for their hands. The crowd braced themselves with rugs, winter jackets, piping hot thermoses and sausages in bread. Lead bails were needed to stabilise the stumps.
The New Zealand bowlers struggled to get the ball through on what is becoming a tame track - but it did not stop Vernon Philander who has been the bowler of the match, consistently generating pace and bounce in an awkward channel. He backed up his four wickets in the first innings with another tidy display which included inducing Guptill to fend a ball to second slip.
The New Zealanders wore black armbands to mark the passing of team manager Mike Sandle's mother.
