The Wallaroos have taken a 21-12 lead over South Africa at half-time in Cape Town.
Jo Yapp's side are coming off a bonus point win over Wales to start the tournament.
Watch the Wallaroos tackle South Africa live and exclusively on Stan Sport.
Cecilia Smith comes into the starting side as flanker Ash Marsters equals the record for most Wallaroos caps.
As for South Africa, they are riding the wave of home support following a narrow win over Japan.
The winner can take outright first position on the ladder, with Scotland holding top for now after defeating Japan.
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45': Desiree Miller races away and flips the field, with a grubber to Maya Stewart under penalty advantage just going dead.
42': The Wallaroos survive as the resulting lineout from the penalty eight minutes out is not straight as the rain starts to come down
42': Atasi Lafai is yellow carded for a high tackle on Chumisa Qawe, with the play staying a yellow card
HT': Atasi Lafai on for Tabua Tuinakauvadra during the break
HALF TIME: WALLAROOS 21 - 12 SOUTH AFRICA
40': WALLAROOS NO TRY: Desiree Miller starts and finishes it as she makes use of a mismatch to sprint past the defence, drawing the fullback for Layne Morgan who is brought down inches before the line, with Miller's second effort denied for a knock on by Morgan in the build-up
36': Both teams throwing the ball around as they look for a crucial try before the break
30': SOUTH AFRICA TRY: Sinazo Mcatshulwa burrows over from close to get the hosts back into it Wallaroos 21-12
26: Australia's turn to burn possession close to the line after a Desiree Miller break, with Eva Karpani putting the ball down
24': South Africa are rolling as they break down the field through Aseza Hele but they give away a crucial penalty five metres out.
21': WALLAROOS NO TRY: Some awesome hands between the backs sets up the counterattack as Stewart makes another break, but Cecilia Smith drops the ball over the line with no one around her!
18': Wallaroos get up and contest a lineout on their line as they stop a strong South Africa attack for now
13': WALLAROOS TRY: Eva Karpani shows off the footwork as she beats some lazy defence to dive over under the posts Wallaroos 21-5
12': Wallaroos pressing for a response as they get the lineout inside South Africa 22
9': SOUTH AFRICA TRY: The hosts erupt the crowd as Caitlyn Halse's clearing kick is charge down and scrumhalf Unam Tose places it down Wallaroos 14-5
8': WALLAROOS TRY: An unreal break from Maya Stewart sets up her good mate Georgina Friedrichs as she beats her defender, bumps off the fullback and gives to her centre for the try Wallaroos 14-0
6': Pesi Palu gets Australia back on the attack after a sharp offload from Ash Marsters, only for her offload back inside to be intercepted
4': WALLAROOS TRY: Siokapesi Palu barges over from short to open the scoring for Australia Wallaroos 7-0
1': Early pressure from South Africa is relieved by a great clearing kick from Faitala Moleka that sets the Aussies up 35 metres out
KICK OFF: We are underway in Cape Town as a loud crowd shows their support for South Africa. The anthems are sung, the countdown is complete and play has commenced
Tries: Palu, Friedrichs, Karpani
Cons: Moleka 3/3
Tries: Tose, Mcatshulwa
Cons: Roos 1/2
WALLAROOS (15-1): Catilyn Halse, Maya Stewart, Georgina Friedrichs, Cecilia Smith, Desiree Miller, Faitala Moleka, Layne Morgan, Tabua Tuinakauvadra, Ashley Marsters, Siokapesi Palu, Michaela Leonard (c), Kaitlan Leaney, Eva Karpani, Tania Naden, Bridle O’Gorman
Replacements: Tiarna Molloy, Lydioa Kavoa, Allana Sikimeti, Atasi Lafai, Lucy Dinnen, Samantha Wood, Trilleen Pomare, Lori Cramer
SOUTH AFRICA (15-1): Eloise Webb, Jakkie Cilliers, Zintle Mpupha, Chumisa Qawe, Ayanda Malinga, Nadine Roos, Unam Tose, Aseza Hele, Sinazo Mcatshulwa, Lusando Dumke (c), Vainah Ubisi, Danelle Lochner, Babalwa Latsha, Roseline Botes, Sanelisiwe Charlie.
Replacements: Micke Gunter, Yonela Ngxingolo, Azisa Mkiva, Nolusindiso Booi, Catha Jacobs, Sizophila Solontsi, Felicia Jacobs, Byrhandre Dolf.
Referee: Precious Pazani (Zimbabwe)
Assistant Referees: Amelia Luciano (USA) & Maria Latos (Germany)
TMO: Estelle Whaiapu (New Zealand)
The Wallaroos' clash with South Africa will be shown LIVE on Stan Sport.
Coverage will be live and ad-free on Stan Sport, slated to start at 12:50 am AEST with kickoff expected at 1:00 am.
