Brendon McCullum would have backed his instincts after his side rolled Sri Lanka for 138 in a poor collective first-innings effort.
Fine seam bowling by Trent Boult, in particular, as well as Tim Southee and aggressive back-up from Neil Wagner and Jimmy Neesham had the visitors in deep trouble. And the last Sri Lankan wicket fell just before tea.
McCullum took the final catch, then walked across to Southee, the leader of the fast-medium group and had a quiet word, shortly before McCullum signalled his intentions to the Sri Lankans. The conversation may have gone along the lines of, 'How you feeling, champ?'
Southee, who with Boult had been kept away from the bowling crease for the previous 50 minutes, presumably said they'd be good to go.
"We had them 120 for nine and it was a pretty clear-cut decision," Boult said.
"It was starting to cloud over and we were pretty confident it was going to swing around and it definitely did that. They played it extremely well.
"We had a lead of 303 and thought we were in a good position and still believe it was the right decision."
McCullum has recent follow-on experience in home tests, having done it twice against the West Indies last summer. It backfired at Dunedin in the first test when Dwayne Bravo's double century held things up long enough to leave New Zealand 33 runs short when the anticipated rain arrived.
At the Basin Reserve a few days later, he repeated the move and Boult and co made short work of the feeble West Indian batting a second time. One train of thought might have been that the pitch, making its test debut, was still helpful for seamers and the Sri Lankans were staggering.
However, openers Dimuth Karunaratne and Kaushal Silva showed more backbone in the final session and got good reward to keep their side afloat.
Karunaratne had a couple of lives - at 10 he was dropped at mid-wicket by substitute fielder Cole McConchie off Boult, and Boult later got a hand to what would have been another special at point off Wagner.
The morning belonged to Boult, who needed four balls to become the 13th New Zealander to snare 100 test wickets. He had the great Kumar Sangakkara athletically caught at third slip by Southee in a devastating seven-over spell of three for 11. In taking the catch, Southee split the webbing between thumb and forefinger on his left hand and needed five stitches.
Southee joined in after lunch before Wagner, with three wickets in 13 balls, and Neesham wrapped it up with more muscular methods.
Sri Lanka's captain Angelo Mathews is in rare form and added another 50 yesterday. Since June, he has scored 796 runs at 88 in 13 innings. He looks a resourceful, skilled batsman but had a woof at Wagner and gave away his wicket.
Sangakkara's recent record against New Zealand is ordinary. His last four scores are 5, 0, 16 and yesterday's 6.
Then again, he's the world's No1-ranked batsman and, for all the praise heaped on McCullum's feat of getting to 1000 test runs 24 hours earlier, it's worth recording Sangakkara has hit 1437 this year, with one innings left.
It will come today and, with another test win beckoning, New Zealand will be on guard.
