NEW ZEALAND kept the third Test against South Africa on a knife edge on the third day in Hamilton, as the hosts grafted their way to a first innings lead, closing on 321 for four.
Skipper Kane Williamson was the chief architect of the Black Caps' reply, with a record-equalling 17th Test century, and he remains unbeaten on an increasingly fluent 148.
His century saw him level with Kiwi great Martin Crowe, though the 26 year-old still has plenty of years to build considerably on his haul.
There was also a painstaking 88 from Jeet Raval, whose patience and concentration was remarkable in itself. Raval had added 83 with Tom Latham for the first wicket, before the latter was undone by a fine piece of cricket from Morné Morkel.
With Latham happy to shoulder arms to balls slanted across him, the Proteas beanpole switched to round the wicket, and produced a gem of a ball, that pitched and then held its line.
Latham nicked off, and Quinton de Kock's diving catch completed a beautifully constructed dismissal by the South Africans.
It was, indeed, a fitting way to bring up Morkel's 250th scalp at Test level. Morkel also had Raval caught behind, with the Kiwi's patience running out with a Test ton on the horizon.
By then, Raval had added 190 with Williamson, the bulk of the scoring coming from the skipper.
On a slowish pitch, Williamson played late, but with comforting certainty, displaying why he is one of the most highly regarded of players in the modern game.
His flat, pulled six off Morkel was one of the shots of the summer, as he finally came into his own in the series.
Kagiso Rabada, bowling with good pace all day long, got his reward late in the day, with the scalps of Neil Broom and Henry Nicholls.
With rain anticipated on the fourth day, New Zealand’s efforts may yet come to naught, buy they certainly can't be accused of a lack of trying.
If the final Test is to have an outright result, there will have to be a collapse from one of the sides, on a pitch that has draw written all over it.
New Zealand seem intent on batting once and batting long. And, as long as the brilliance of Williamson remains at the crease, they will have hope of squaring the series – if the elements provide a big enough window.
The Black Caps, as is their nature, will keep scrapping to the final whistle, even if the weather looks set to spot what would have been an interesting finish to a cracking tour.
South Africa lead the three-match series 1-0.