Teenage wing Braxton Sorensen-McGee scored a hat-trick of tries as reigning world champions
New Zealand showed their class to beat Ireland 40-0 and secure top spot in Pool C.
Both sides had already booked a quarter-final spot but New Zealand dominated the game from the moment Stacey Waaka crossed for the opening score after she was set away by Sorensen-McGee.
Prop Chryss Viliko added a second, and then Sorensen-McGee scored the try of the half as she beat three players to give New Zealand a 19-0 lead just before half-time.
Sorensen-McGee scored her second try of the game with 22 minutes remaining and the 18-year-old completed her hat-trick before Maia Joseph added some gloss in the final minute.
It is a first defeat of the tournament for Ireland, who will now face the winner of France and South Africa at 16:45 BST.
As well as securing the theoretically easier quarter-final tie, against the loser of the Pool D decider, New Zealand also got revenge on Ireland for the defeat in WXV1 last October.