We need to talk about Tim Southee. His batting suffered a jump-the-shark moment in the test at Pretoria but it is his bowling that should concern his coach and captain the most.
How South Africa managed to score 481-8 on a difficult Centurion wicket is almost beyond analysis, suffice to say they had a lot of luck and a huge helping hand as they cruised to 133-0 in the first session or so.
Southee's 2016 test numbers are unhelpful, even taking into account the nice little boost they've received from South Africa's devil-may-care second innings in Pretoria.
He's taken 14 test wickets while conceding 646 runs in 211 overs. He hasn't been tight and he hasn't been penetrative. It's a quinella of ineffectiveness.
Trent Boult has endured his struggles as well, though he at least looks like he's returning to somewhere near top pace. Still, his 16 wickets this year have come at a costly 38.
That's your two opening bowlers, the tone-setters, right there.
This is all in stark contrast to Neil Wagner, who has 27 test wickets for the calendar year at an average of 18.6 and an economy rate of 2.6.
It would be a stretch to say Wagner is a better bowler than Southee but it is not a stretch to say he is used a lot more effectively.
There are better minds than mine who are questioning why Southee gets handed the new ball as a right. With the year he's had, you have to ask whether he'd be better employed as a first-change bowler, giving somebody else the chance to knock the top off the opposition.
Discounting the virtual rain-out in the first test of this series, New Zealand has put in three successive lousy test performances. Southee's struggles with the new ball have been a common denominator.
He has enough credit in the bank to retain his place in the XI, but New Zealand need to reassess how they configure their attack. It would be insanity to keep doing the same thing expecting different results.