England back Sarah McKenna has called on the Red Roses to show a ruthless cutting edge when they play South Africa in their final pool game.
But coach Simon Middleton warned his side that they were "one bounce of the ball" away from defeat despite having 70% of territory and 67% of possession.
"It is important to go in and get a third win, but how we get that win is really important," said McKenna.
"The way we want to execute is to be better at finishing than we were in the France game."
McKenna is one of eight players who could get their chance to stake a claim for the knockout stages after sitting out the first two matches.
Middleton made just one change to the matchday squad that beat Fiji on the opening weekend for England's win over France.
He will name his side to face South Africa on Thursday evening UK time.
England, who are on a run of 27 straight victories, have not played South Africa, ranked 13th in the world, since 2013.
The Springbok Women instead took on an England under-20 team during their northern hemisphere tour in 2021, winning 38-5.
"We are playing a group of superstars in the England squad, so the trick will be not to be over-awed by the status of your opponent, but to rather believe in the team effort," said South Africa scrum-half Tayla Kinsey, as her side attempt to bounce back from defeats by France and Fiji.
"Catha Jacobs (Saracens) and Zintle Mpupha (Exeter Chiefs) did play in the Premier 15s, so they can give us more information on our opponents, should we wish, but ultimately we need to focus on ourselves first."
Supporting the support staff
McKenna is in charge of organising the Red Roses' social activities, but admitted the most fun off-field experience so far in New Zealand was not one staged by her.
England physio Kate Tyler had been due to run the London Marathon before being called up for the tournament.
Instead she ran 26.2 miles around the team's base in Whangarei, with the players cheering her from start to finish.
"We all got well behind it and made lots of posters, made her a podium at the finish and lots of banners to run through," said McKenna.
"That was really fun. It was really nice for once to be supporting someone else. You realise how good it feels to support someone else and their achievements and that can make you really happy as well."