As it is, Australia will start day three just seven behind New Zealand's first-innings 370 with six wickets standing and well in charge.
But Wagner at least lightened the mood after it seemed Australia would be some way ahead by stumps and so New Zealand will start today with a sense of optimism.
The day belonged to Australian batsmen Joe Burns and captain Steve Smith, who shared a 289-run third-wicket partnership to shut the door on New Zealand.
It eclipsed the old Australian record against New Zealand - 264 by brothers Ian and Greg Chappell at the Basin Reserve in 1974 - and was a demonstration of high-class batting, albeit in a distinctly different vein to New Zealand's display on Saturday.
Australia is yet to hit a six in this innings; New Zealand clouted 12 on Saturday.
This was measured batting, assertive and watchful by turn. The whiff of anticipation in the full house of 8000 was palpable when Usman Khawaja was out in the fourth over of the day.
That was steadily worn down by Burns and Smith, who did not give a chance, before Wagner lifted the New Zealand spirits near the end.
Their innings' were a study in contrasts. Burns is a doughty scrapper who got a terrific reward, 170, for his diligence after seven hours, 20 minutes at the crease; Smith was all class.
The skipper is the world's No1-ranked test batsman and yesterday in his 138 showed why.
His technique and constant tugs and twitches make him an intriguing watch, but the thing you most notice is how often the ball hits the middle of his bat. Ultimately that is all that matters.
Burns got a reprieve at 35 after being given out off his shirtsleeve by umpire Ranmore Martinesz; Smith's worrying moment was being struck on the back of his head by Wagner, at 78.
The pair were helped at times by New Zealand's seamers straying off line too often, but they cannot be faulted for not trying various ruses to try to break the stand.
Wagner bowled a short-of-a-length spell with six fielders on the on side; bowlers were tried at both ends. But the balls are not swinging this season and Brendon McCullum's hope that the pitch would continue to help the seamers was dashed.
So did New Zealand err in not selecting a specialist spinner - and think legspinner Ish Sodhi rather than offspinner Mark Craig, who has been cleaned up by the Australians this summer?
Four seamers was not an unreasonable call but an XI with a specialist spinner is always preferable, just in case that first day deep green hue of a pitch proves misleading.
But it has left them short in the spin cupboard with only the occasional offies of Kane Williamson for relief.
It was puzzling, too, that senior seamer Tim Southee was not called upon with the second new ball until the 13th over. Still, New Zealand is alive in a test it must win to square the series.
The first session today is vital.
‘‘We know New Zealand will come hard searching for wickets,'' Burns said.
‘‘You just try and bat for as long as possible. There is no rush to score runs, it's probably just a matter of occupying the crease.''And after yesterday, he is an authority on that.