The Proteas top order, led by De Kock’s 82, took full control on day one of the second Test against NZ as they piled up 282-3.
All the top four passed fifty after they were put in on what was expected to be a tricky wicket.
Hashim Amla picked up the gauntlet after the openers had built a foundation of 133, finding superb rhythm to ease to 58 off 91 balls. He and JP Duminy put on 95 for the third wicket, until Amla was undone by an unplayable ball from Neil Wagner.
Undaunted, Duminy went on to 67, his first Test fifty in two years, ending the day alongside Faf du Plessis, who was muted in his approach, scoring 13 off 58 balls.
Kane Williamson will rue his decision to put the Proteas in to bat, although it seemed a good idea at the time, with the strip having a generous covering of grass. Indeed, it might have been different when they appealed for lbw against Stephen Cook in the fourth over of the day, but the review picked up the inside edge.
It may have been different too, if the Kiwis had taken the few opportunities on offer, and a more judicious use of the review. But having lost one to Cook, they were too cautious and spurned opportunities which would have dismissed both Cook, on 36, and Duminy, on 20. In between, BJ Watling dropped De Kock on 46 when a thick inside edge had the keeper diving despairingly to his right. In contrast, Amla and Duminy reviewed lbw decisions and both were successful.
The imposing total was built on the patience and resolute defence of Cook, playing a paternal anchor role, and De Kock, who had been promoted to No 1 after Dean Elgar was injured in fielding practice on Friday. Stiaan van Zyl replaced him and was placed at No 7.
They had a few nervous moments from great deliveries in the first session – more than one boundary came from an edge – but they were prepared to wait. Those two took the score to 100 off the last ball of the morning session, and De Kock particularly came out firing in the second session. He was looking good when he slightly mistimed a pull off Wagner for Boult to pocket, peddling back furiously on the boundary. His 82 contained 15 fours, striking at a rate of just on 72.
When Cook went, caught in the gully for 56 off 142 balls, the Proteas had to rebuild at 151-2. They did that magnificently until Amla, just after reaching his 76th Test fifty, received a swinging, dipping, unplayable ball from Boult, which faintly nicked off to Watling. He had nine fours and a six within the 91 balls he faced.
The Proteas are now set for a big total.