Tactically New Zealand were smart today. They have played this test really well. They didn't rush headlong for frenetic runs when they began at 321 for four today, seven ahead.
The batsmen had to work hard early, the approach was measured and they didn't panic when captain Kane Williamson departed before lunch, crestfallen at hooking Morne Morkel to fine leg after a memorable 176.
Mitchell Santner played a significant hand and none did better than Colin de Grandhomme, who tempered his preference for Route One hitting and was rewarded with his maiden test half century, 57 off 70 balls. This was the innings the selectors have been waiting all summer to see from him.
The upshot was that South Africa, after 162 overs in the field, and basically knackered at the end of a a summer equally as long as the hosts, found themselves having to bat four sessions to secure the series.
Runs equal pressure and South Africa started out with no real interest, or need, to pursue a win. That changes the mindset and the approach.
Matt Henry nudged the door open, removing the out-of-sorts Dean Elgar, before South Africa gifted New Zealand a momentum-grabbing bonus.
A botched single, where Hashim Amla and debutant Theunis de Bruyn collided in mid-pitch, cost de Bruyn his wicket.
Offspinner Jeetan Patel then stepped up, taking two wickets in 12 balls, including JP Duminy - who had survived two DRS referrals, admittedly poor calls from a New Zealand team who really haven't got that issue right all summer - inexplicably shouldering arms.
When Temba Bavuma touched a catch to the wicketkeeper and immediately put his bat under his arm and marched off, old school style, South Africa had lost three for 10 in 42 balls.
New Zealand tails up? Not half, and there's good turn in the pitch, but there'll be no pre-emptive high fives. They've worked too hard to get back into the series at the last opportunity for that.
''It was a bad day. We have got a mountain to climb," South Africa's assistant coach Adrian Birrell admitted tonight.
South Africa's lowest total against New Zealand is 148 at Johannesburg in 1953. That's under serious threat.
''To get five tonight is a good start," Patel said. ''We'd love to have got one more.
''This is a pretty important partnership. We know they can grind us down and score at a rate that'll make it difficult if we need to chase anything at the back end."