Police were speaking to the driver of the car as part of their inquiries.
Inspector Srhoj said the incident was entirely preventable.
“Police have been warning the community that something like this could happen and unfortunately we now have a woman in Middlemore Hospital with serious injuries.”
Fans have been taking to the streets in town centres across Auckland during the tournament in the United Kingdom.
Police have been monitoring the celebrations.
“It is an incredibly exciting time for league fans as the business end of the tournament nears, but our plea is that they consider everyone’s safety and the wider community,” Srhoj said.
“Our concern continues to be that dangerous activities or unlawful behaviour could lead to further serious or fatal injuries.”