Should the Ferns gain all three points and leapfrog the Chinese, their placing will depend on the result of Canada's clash with the Netherlands in Montreal.
The hosts have four points while the Dutch, like China, have three, meaning New Zealand could move as high as second with the right result.
A third-placed finish with four points should earn a place in the Round of 16, against the winner of either Germany's or USA's group, while finishing in second place would book a date with Switzerland or Cameroon.
"It's going to be a game where both teams are fully committed to getting the result they need," said Readings. "It's two teams who have been pretty close in the past in terms of performances and results so hopefully it will be a good show.
"We haven't scored in the first two games but we feel we have created enough chances.
"If you look across all the teams in our group we are very closely matched so there hasn't been an abundance of chances for anyone."
With a defence that has been breached only once - only Brazil and Canada have conceded less - Readings says the difference between progression and an early exit could be a moment of magic.
"One chance could make the difference.
"It's a chance for someone to step up and be that game-breaker for us, find that little bit extra, a piece of skill that turns the match our way."
