Australia level the summer series after Wales won 21-12 in Brisbane on Saturday.
Maya Stewart scores opening try on return for Wallaroos.
Jaz Joyce responds with score on her 50th cap for Wales.
Faitala Moleka grabs hosts' second try before hooker Katalina Amosa dives over on stroke of half-time.
Tabua Tuinakauvadra barges over twice in the space of six minutes early in second half.
Those tries came either side of yellow card for Wales prop Gwenllian Pyrs.
Ashley Marsters crosses late for hosts' sixth try but has a second ruled out that would have clinched a record win for Australia over Wales.
Faitala Moleka (Samantha Wood con)
Australia have shown Wales how to be clinical with two try opportunities and two tries.
Fly-half Faitala Moleka glides over while half-back partner Samantha Wood slots over the conversion.
Image source, Getty ImagesAustralia 7-5 Wales
Sioned Harries
Former Wales back row on BBC Cymru Fyw
All it took was half a gap, and she got through.
That was all in the build-up play and their ability to change the point of the attack.
I'm sure that felt like a relief for Wales, they finally turned an opportunity into a score.
Jasmine Joyce-Butchers
Who else but the Wales wing Jasmine Joyce-Butchers on her 50th cap? That was reward for all the pressure Sean Lynn's side had inflicted on the hosts.
Keira Bevan misses the conversion.
Australia 7-0 Wales
It was a well-worked out line-out move, yes, but they lose possession from another one as their pressure is not telling yet.
Australia 7-0 Wales
Caryl James
Former Wales wing on BBC Radio Wales Extra
What a move from the lineout that was.
Australia are just doing enough to keep Wales at bay, they're doing a great job of breaking up Wales' rhythm.
Australia 7-0 Wales
It is normal service resumed as Wales attack again but they spill possession in the Australia 22.
Australia 7-0 Wales
Ceri Coleman-Phillips
BBC Sport Wales rugby reporter at North Sydney Oval
I've been keeping a close eye on the tunnel to see if Alex Callender emerges, but nothing so far.
These are worrying times. Hopefully she's just staying out of the rain.
Australia 7-0 Wales
Alisha Joyce-Butchers
Wales flanker on BBC Sport Wales
It's great to see Australia able to move the ball quickly in these conditions, it's not easy to do that when it's like this.
Image source, Getty ImagesMaya Stewart (Samantha Wood con)
That came against the run of play but Australia create an overlap in the right corner and it is the prolific Maya Stewart who scores.
Image source, Getty ImagesAustralia 0-0 Wales
Australia have their first period of pressure as they test the Wales defence and force the visitors to concede a penalty in their own 22.
Australia 0-0 Wales
Caryl James
Former Wales wing on BBC Radio Wales eXTRA
That was brilliant scrummaging there from Gwenllian Pyrs.
I'm not quite sure how the referee has come to that decision.
Australia 0-0 Wales
Wales were going forward in a scrum in the Australia 22 but somehow they were penalised and the hosts have a chance to ease the pressure.
Australia 0-0 Wales
Caryl James
Former Wales wing on BBC Radio Wales Extra
This is an excellent effort from Wales, you'd think they will be rewarded soon.
Image source, Getty ImagesAustralia 0-0 Wales
Alisha Joyce-Butchers
Wales Flanker on BBC Sport Wales
Wales will be disappointed they didn't come away with any points from that phase of play.
But it's still early in the game, and they will stay in the Australia 22 from the drop-out.
Australia 0-0 Wales
Wales have produced a lot of pressure on the Australia line but prop Gwenllian Pyrs was held up and the hosts survive.
Australia 0-0 Wales
Wales have started this game well. They have kept possession and forced Australia to concede a penalty which sets up an early chance for Sean Lynn's side.
Image source, Getty ImagesAustralia 0-0 Wales
Caryl James
Former Wales wing on BBC Radio Wales Extra
Wales have kept the ball really well so far, we've had some good carries from Sisilia Tuipulotu and Gwenllian Pyrs.
Because they're so dominant in the carry, they're able to offload the ball nicely as well.
Australia 0-0 Wales
This is a sad moment for co-captain Alex Callender who is forced off injured and replaced by Georgia Evans.
That will be a concern before the World Cup later this month.
Australia 0-0 Wales
As you would expect, there is a lot of kicking early on in these tough weather conditions.
Both teams are sounding each other out before Jasmine Joyce-Butchers produces a great run. Unfortunately for Wales the ball is turned over.
Australia 0-0 Wales
Wales were led out by Jasmine Joyce-Butchers on her 50th cap.
After the anthems where both sides were looking very relaxed and composed, New Zealand referee Natarsha Ganley blows the whistle and Australia gets us under way in Sydney.
It is raining hard out in Sydney with standing water on the field.
