Australia 207 and 5 for 57 (Cross 3-13) need another 128 runs to beat England 201 and 190 (Edwards 56, Perry 5-38)
In an exciting day of Test cricket, which ebbed and flowed to a dizzying extent, Australia collapsed to 5 for 57 chasing just 185 as England struck repeatedly with the new ball in the final 90 minutes of play. The crucial breakthroughs came via Kate Cross, whose consistent line once again belied her debutant status, as she took wickets in successive deliveries. Five balls later Cross struck again, handing Alex Blackwell a pair for the match.
Australia had moved swiftly to 0 for 28 in six overs, before Katherine Brunt checked their progress, as Elyse Villani chanced one too many and skied the ball in the air, giving Natalie Sciver, moving forward from second slip, an easy catch. In the wake of Cross' burst, Jenny Gunn, who had proved vital at stemming the flow of Australia runs - she conceded just two off seven overs - then had Jodie Fields stumped for 13, the batsman lifting her back foot off the ground as she played a defensive stroke.
Ellyse Perry, who rescued Australia from a similar predicament in their first innings, batted to the close alongside Sarah Elliott, with the match delicately poised.
Having begun the day in a precarious position, three wickets down and just 12 runs ahead, England were indebted to Arran Brindle and Sciver, who extended their fourth-wicket partnership to 54 during in the morning session. Fields' tactics of short, attacking bowling with a loaded leg-side field failed to bear fruit, as the two quicks Rene Farrell and Holly Ferling struggled to bowl to plan, with both punished through the covers by Brindle as a result.
Perry, whose all-round contribution has been impressive, struck just before lunch with two quick wickets, bowling Sciver and having Brindle lbw for 35. But even Perry could not manage long spells in the Perth heat. England had toiled in the field on the second day; now it was Australia's bowlers who grew gradually more exhausted and frustrated in the hour after lunch, during which Perry did not bowl an over.
Sarah Coyte and occasional spinner Elliott failed to hit the right line as Charlotte Edwards, batting at No. 7 after a knee injury kept her off the field on Saturday, proved she was fully recovered with a series of lovely strokes around the ground. Gunn, who made her highest Test score of 44, proved an able partner at the crease.
Edwards had reached 56, her ninth fifty-plus score in an Ashes Test (more than any other woman), before Perry was brought back into the attack. She struck immediately with an inswinger that did for Edwards, hit on toe in line with leg stump. Danielle Hazell was then dismissed by Coyte to a poor shot, nicking a wide one, and when Gunn was out in the last over before tea, caught behind off the bowling of Erin Osborne, England led by 171.
The tail frustrated Australia for a while longer, with Brunt surviving 47 balls to finish not out, but only 13 runs were added before England's last two wickets fell, with Perry completing a maiden five-wicket haul in Tests. England's second-innings total of 190 was short of the runs they needed to feel confident of victory, though was in keeping with what had gone before in this match.
Australia made the chase look easy in their first few overs, racing off to a fast start as Villani took nine off the first over from Brunt, followed by three successive boundaries off the bowling of Shrubsole. But then the wickets tumbled. As it is, it will require a big effort from Perry - who bowled 20 overs in the innings, to go with 22 in the first, and must be exhausted - for Australia to win this Test and take the six points on offer in the Ashes series.