The strength of a team's character, Graeme Smith used to say, is not seen when they scale a peak but when they remain steady at the top when strong winds threaten to blow them off. Smith was speaking figuratively after South Africa took the No.1 ranking from England in mid-2012. South Africa were acting out those words literally in Wellington almost five years later, where they are no longer the holders of the mace but pushed a position of authority so hard that they inflicted defeat on New Zealand inside three days to take an unassailable advantage in the three-match series.

Let's start with the wind. It was blowing from the south, the Antarctic, and filtering through the Cook Strait at speeds of around 50kph. So it was not just a wind but an icy scythe cutting through everything but the enthusiasm of the Wellington faithful, who arrived at the Basin Reserve with blankets to put over their singlets and shorts. South Africa, though, were more sensibly dressed.

Their bench-warmers wore soft-shell jackets, beanies and gloves. On the field, Kagiso Rabada, big, strapping Kagiso Rabada, had hand-warmers in his pockets and he held on to them like a kid to his security blanket. Faf du Plessis also had them in his pockets and when one of the warmers broke, it leaked a dark substance onto his fingers. Thank goodness du Plessis did not go near the ball with that.

And there were real consequences attached to this cold. When JP Duminy dropped the catch that would have dismissed Jeet Raval on 53, he immediately looked at his fingers, as if to blame them. Stephen Cook, who put Raval down at square leg on 76, was more stoic but there was more hand-rubbing than wringing in response. Temba Bavuma joked that he would have to bat with bricks in his pockets to avoid being blown away in the Wellington southerly. Would Keshav Maharaj need a whole house? Although not as short as Bavuma, Maharaj is certainly lighter. And he would have to do more than just keep himself upright, he would have to control a ball too.

Being a spinner on a cold, windy day isn't easy. Being a spinner in a South African attack, who tend to view their slower bowlers as gatecrashers at a private party, isn't easy either. And being a spinner on a pitch that showed no signs of deterioration early on and was as green as the outfield wasn't supposed to be easy. But with a bit of drift, an inviting line outside off and some help from New Zealand's batsmen and his own quicks, Maharaj must have wondered whether this gig was really as tough as it was made out to be.

After Maharaj tried to lure Neil Broom and Raval into a mistake, he succeeded in getting first-innings centurion Henry Nicholls to make one. The positivity Nicholls showed on the first day was misused on the third when he reached for a sweep and played on. That brain fade opened the over, Jimmy Neesham's closed it. Knowing the situation called for some responsibility, Neesham stepped down the track and tried to flick Maharaj over midwicket where he was met by a Plessis one-handed signature stunner. New Zealand were effectively -1 for 5 at the end of that over and mostly had themselves to blame.

As did Raval when he threw away the chance at a first hundred by making almost the same mistake Neesham did by stepping out, but instead of hitting the ball, he missed and was stumped. As did Tim Southee and BJ Watling, who both holed out when the heat was on. The only New Zealand batsman who was outfoxed by a delivery, and not by a tactic to force a mistake, was Colin de Grandhomme, who received a ripper that turned passed the outside edge and hit the top of off.

So why did the rest allow Maharaj, who bowled 14 overs into the wind, to make such a mess of their attempts to set a target? Because at the other end, Vernon Philander, Morne Morkel and Rabada were operating. Philander has bowled brilliantly throughout the two Tests with scant success; Morkel has returned to greater rewards and has used his aggression well and Rabada's pace is unmatched. Yet, Maharaj has more wickets than any of them. For a change, the quicks were creating pressure so the spinner could profit. How South African cricket has changed.

The last time a South African spinner took six wickets in an innings was eight years ago: Paul Harris against Australia in Cape Town. The last time a South African spinner took consecutive five-fors was 14 years ago: Paul Adams against Bangladesh in 2003. And the last time a South African spinner took 15 wickets in a series was 16 years ago: Nicky Boje West Indies. Maharaj has already bettered the first two and with 13 wickets so far he could overtake the third too. Those numbers are impressive but they don't fully explain what Maharaj adds to this attack: certainty.

While Adams lost his mystery, Boje and Harris did their job without setting the world alight. In searching for someone with a bit more spark, they moved on to Imran Tahir who tried so hard and got it so wrong that they went all the way back to Robin Peterson. Dane Piedt was an interesting experiment and that may continue as early as next week in Hamilton, where South Africa are expecting a turner. But there is no doubt that Piedt is No. 2.

The No. 1 is a character whose confidence in his on-field performances - even with bat in hand Maharaj isn't afraid to give it horns - morphs into boy-scout bashfulness off it. He is a man who has mastered the role of a South Africa spinner which is mostly a behind-the-scenes one but can step up when needed. He is the one who withstood the wind.

Firdose Moonda is ESPNcricinfo's South Africa correspondent