Blackcaps quick Neil Wagner says the Kiwis never gave up in the field despite fierce criticism from former captain Brendon McCullum.
The trans-Tasman series is slipping away from New Zealand as Australia racked up 467 after being sent into bat at the Melbourne Cricket Ground (MCG).
In New Zealand's first Boxing Day test in 32 years, they will face an uphill battle to save the match from 44/2 and avoid Australia taking an unassailable 2-0 series lead.
It led McCullum to tee off on his former side, saying the Blackcaps "rolled over" in the field as Tim Paine and Travis Head piled on runs on Friday.
He said it was a "staggering" move from captain Kane Williamson to bowl part-time spinner Tom Blundell straight after the lunch break instead of their frontline bowlers.
Blundell, whose only two previous test matches were as a wicket-keeper, has just one first-class wicket to his name.
"I think it's been another pretty poor session. I don't understand some of the tactics, to be honest," McCullum said on SEN Cricket.
"It's just staggering. The game is still in the balance, to me it was a submissive move [to bowl Blundell].
"Not only just bowling [Blundell], but Kane Williamson has 29 test wickets to his name. Tom Blundell wouldn't have bowled in the nets."
But the tireless Wagner, who finished with 4/83 from 38 overs, said one thing that couldn't be questioned about the Blackcaps is their spirit.
"I thought we kept fighting, we kept trying and that's one of the great characteristics about this team is that we kept giving everything, even in the field," he said.
"Full credit to Australian batsmen, they've almost been like a step ahead of us. They've played really well and showed a lot of patience."
Blundell's spell raised even further concerns about New Zealand's frontline spinner Mitchell Santner, who bowled just 20 of the 155 overs in the innings for figures of 0/82.
Former New Zealand pace bowler Simon Doull said the Kiwis faced a "problem" with their spin option.
"I can almost guarantee that if Australia had bowled close to 150 overs then Nathan Lyon would have bowled nearly 40 of them," he said.
AAP
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