What a wasted opportunity the New Zealand first innings was. When Brendon McCullum and Ross Taylor were together, the Black Caps had a golden chance to work towards a decent lead.
The lead they should have got would have made it very hard for South Africa to set them a target loaded in the visitors' favour. However, even with that opportunity lost, this target is very gettable today.
Why did McCullum and Taylor play poor shots in that first innings? Only they will know. They weren't poor shots in terms of decision-making but rather execution.
That seems to be the main issue with the Black Caps batting in test cricket. They all seem to find a way to get out too regularly - though our hopes of saving or even winning this test today likely rest with that same pairing.
If they want a demonstration of quality execution over long periods, then McCullum and Taylor's counterparts Jacques Kallis and Graeme Smith provided it.