The margins are slim in South Africa this past fortnight and not just on the scoreboard. According to aviation experts, one of the two planes flying over the stadium in Cape Town just before kick-off on Saturday came within 12 to 14 metres of hitting the top of the stand which, depending on your perspective, either ranks as highly-skilled piloting or the most gratuitous of matchday stunts.

Something similar could be said, as it happens, about Rassie Erasmus’s ongoing selectorial high jinks. His initial starting XV announced for the second Test bore about as much resemblance to the one that ultimately took the field as Erasmus did to the late, great Dolly Parton, with no fewer than six of the original lineup missing. It had the desired result in terms of South Africa levelling up the four-Test series at 1-1 but was yet another example of Erasmus toying with the game’s supposed conventions.

Under World Rugby regulations, teams normally require medical dispensation to change their team within 48 hours of kick-off but “Rugby’s Greatest Rivalry” is an independently administered competition so Erasmus can make as many late changes as he fancies including, in this case, switching his entire front row before kick-off. A change in weather conditions was the supposed catalyst but, as ever with Erasmus, it felt as if wider-ranging “mind games” were involved.

There is a broader debate to be had about all this – football managers do not declare their line-ups until an hour before kick-off so, in theory, why should rugby be any different? – but that also suits the artful Erasmus just fine. By naming his team on a Monday he immediately hijacks the narrative; by changing it later in the week he can do so again. How many more column inches and social media posts have been focussing on the latest update from the world champions rather than the reinvigorated attacking threat posed by New Zealand?

The All Blacks, to borrow one of Dolly’s iconic lines, have certainly poured themselves a fresh cup of ambition since Dave Rennie took over as head coach. In both Tests to date they have won the try count which currently reads 9-4 in New Zealand’s favour. Yes, the visitors need to improve their lineout and restart percentages and not get smothered by the Bok scrum but they are not a million miles away. Compare and contrast the All Blacks’ second half doggedness and line-breaking ability across the opening two weekends of the series with, for example, England’s collapse to a 45-21 defeat in Johannesburg in July.

The 16-million rand question – the local exchange rate to the dollar is not what it was – is whether or not Rennie’s men can box clever again in Soweto this weekend and confound the significant weight of Springbok history. Remarkably New Zealand have never won a multi-Test series in South Africa when their hosts have claimed one of the opening two Tests; the closest the All Blacks came to doing so was a 2-2 drawn series in 1928.

Whenever Ardie Savea has the ball anything is possible and it says plenty for the rising profile of Fabian Holland that he would not look out of place in a Springbok second-row jersey. Cam Roigard at scrum-half has also been excellent and in terms of swift midfield hands giving outside runners a crucial extra half-yard of space New Zealand are now right back up there with the best in the world.

The problem is that South Africa will not be as sluggish again as they were for lengthy chunks of the first Test. People can say what they like about Siya Kolisi but his return as captain visibly improved his team’s collective body language in Cape Town, albeit out of necessity.

If there is a degree of frustration that, in many ways, South Africa have largely reverted to type for this “Greatest Rivalry” series there is equally no doubt about the physical clout they continue to wield. How good was Malcolm Marx on Saturday following his belated arrival off the bench and what a remarkable presence Peter-Steph du Toit continues to be. Over four Tests, too, the Boks’ forward strength in depth is going to be hard to resist, particularly if Eben Etzebeth replicates his second-Test display.

The referee Nika Amashukeli, ruled out of the second Test through illness, has also become something of a lucky charm for the Boks, having presided over their 43-10 annihilation of New Zealand in Wellington exactly a year ago. It will be no surprise if Erasmus slyly points out that fact this week; love or hate the way he operates, he misses absolutely nothing.

True to form, he was back on the front foot on Monday, once again unveiling his side early – or at least a first draft of his teamsheet – and predicting New Zealand will come even harder this time. “We know how it felt after the first match in Johannesburg and such a result really galvanises a team,” warned Erasmus. “This game is going to be equally, if not more intense than the last two.

“They are one of the two best teams in the world and, based on experience, they never give up. After two games we are both into hard Test rugby mode and have a good idea of what to expect from one another so it is going to be another grind of a match.”

No mention there of inferior try counts and deliberately so. Come hard from the start – Erasmus won’t be swapping his nominated front row this week – and compete well in the air, backed by an unyielding defence, and New Zealand really will have to pluck something special out of the thin Johannesburg air. If Rennie and co can dodge all that and head to the final Test in Baltimore 2-1 up in the series it will rank among the greatest of modern-day heists.

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