England thrashed South Africa to top Pool C and set up a World Cup quarter-final against Australia next Sunday.
A much-changed Red Roses side ran in 13 tries as they overwhelmed a spirited Springboks side in Auckland.
Second row Rosie Galligan - one of six England players making their first appearance in the tournament - was driven over for the first of her three tries after six minutes.
Hooker Connie Powell rounded off her own hat-trick in the 69th minute.
Sadia Kabeya dotted down to complete an emphatic win.
England's victory also confirms Wales' place in the last eight where they will face hosts New Zealand on Saturday.
The Red Roses have extended their record streak to 28 successive wins and are now potentially three matches from Rugby World Cup glory.
They last played their last-eight opponents Australia back in 2017, winning 53-10 in the International Women's Rugby Series in Wellington.
Beyond the Wallaroos lies a potential semi-final with Canada and a 12 November showpiece final, with New Zealand or France the likeliest to prevail in the other side of the draw.
All those encounters will pose a stiffer test than the Springboks.
There were several impressive cameos from South Africa, with number eight Aseza Hele scattering white shirts and wing Nomawethu Mabenge finding a gap early on.
But the team ranked 13th in the world fell well short of England in most departments, particularly the set-piece.
Following Galligan's opener, Poppy Cleall barged over after England had the South Africa pack stuck in reverse at both the scrum and a driven line-out.
The rolling maul delivered another try for Galligan and one for Shaunagh Brown, called into the matchday squad along with Ellie Kildunne after minor injuries forced Vickii Cornborough and Emily Scarratt to withdraw.
After Connie Powell's score, South Africa headed down the tunnel 29 points adrift. And they might still have counted themselves lucky.
Second row Catha Jacobs was one of two Springboks to see yellow before the interval, but could easily have been sent off for a shoulder to the chin of her Saracens team-mate Poppy Cleall.
Powell claimed her second score at the back of yet another driven line-out within a minute of the restart.
With the result beyond doubt, England expanded their gameplan, switching from the straightforward to the sublime and showing the variety that will be needed in the knockout stages.
A delicious piece of interplay with Cleall served up captain Marlie Packer's 27th Test try before Abby Dow and Tatyana Heard sliced up the Springboks to open the way for Galligan to gallop in.
As South Africa tired, the Red Roses made the most of the space with forwards and backs combining to produce their best rugby of the tournament so far.
Cleall was sent over by some smart hands from Heard, before replacement Kabeya capped off a rolling passage of play that swept across the width of the pitch and through a flagging defence.
Dow dived over for the 11th try in a flurry of three scores in five minutes, before Powell and Kabeya's short-range tries piled on more points.
Middleton will have been less concerned with the scoreline though and more interested in the small print of individual performances.
Scrum-half Lucy Packer was quick and clever in her decisions and delivery, while Galligan staked a significant claim to a second-row spot for the knock-out stages.
Heard was a busy, bustling presence in midfield, while Dow and Breach were clinical when supplied ball in the second half.
Some difficult selection decisions await for the coach.
Player of the match - Rosie Galligan
Teams
England: McKenna; Dow, Aitchison, Heard, Breach; Harrison, L Packer; Botterman, Powell, Muir; Galligan, O'Donnell, Talling, M Packer (c), Cleall
Replacements: Cokayne, Cornborough, Bern, Aldcroft, Kabeya, Infante, Scarratt, Rowland
South Africa: Webb; Mabenge, Namba, Qawe, Roos; Jordaan, Kinsey; Charlie, Botes, Latsha, Booi (c), Jacobs, Dumke, Makua, Hele
Replacements: Gunter, Ngxingolo, Mkiva, Mathe, Solontsi, Potgieter, Cilliers, Qawe