“The good thing is that we found a way, but we didn’t play the way we should have.
“We got away from what we needed to do, so we were a little disappointed there. Being rusty is no excuse.
“I think it’s a wake-up call and the girls will think so too. We fought our way back, so we’ll take things away to work on.”
New Zealand were on course for a comfortable day when Stacey Waaka scored after two minutes, but Fiji went goalless after 21 minutes.
Skipper Sereana Naitokatoka made a clever run from dummy half to find Losana Lutu, who scored Fiji’s first women’s World Cup.
When Sienna Laing extended the lead five minutes later, he was suddenly upset.
Waaka scored his second try to close the gap before the break, but Fiji’s solid defense again refused to let go after the break.
But New Zealand piled on the pressure when they equalised, then Zehara Temara took the lead with a penalty kick.
Victory was not secured until the dying minutes when Racene McGregor’s cross led to Leianne Tufuga scoring.
“We didn’t get our hopes up, but they played like they had nothing to lose,” New Zealand player Georgia Hale said. “They definitely tested our waters.
“We had everything and then we lost it. It was an uncharacteristically undisciplined, sloppy game.
“That was the main thing we wanted to do today. We wanted to set the tone for the tournament by being physical and going forward, but we came away with what we didn’t have.
“Then we had to work hard to make up for it. In the end it was definitely luck.”
At the next stage in Group B, New Zealand will face France at home in Christchurch, and Fiji will face Papua New Guinea.