The Kiwis have now lost four matches in a row against the Kangaroos, all in 2016.
Bromwich was unhappy with the lapse in concentration New Zealand showed during the first quarter of the match.
“It is unacceptable to make seven errors in the first 20 minutes,” he said.
“That is what hurt us.” We will learn from this and hopefully we will be better for it.”
The Kiwis were 24-0 behind going into the interval and Bromwich explained how he wanted his men to give it their all in the second half despite the one-sided margin.
“I just told the guys to have no regrets,” he said.
“It was about leaving it all out there for the last 40 of the year.
“This set of guys might not play together for some time so it was important that they all gave a good account of themselves.”