England needed a fourth-straight white-ball victory in order to take things to a decider on Tuesday, but Australia's victory sees them lead 8-6 on points and even if the hosts were to triumph in the final ODI in Taunton to tie the series, Australia retain the Ashes as current holders.

Set another record chase of 283 to win, Sciver-Brunt struck a magnificent 111 not out off 99 balls but could not quite see England over the line with 15 needed from the final over.

Sciver-Brunt, who was dropped on 97 in the penultimate over the ball before bringing up her ton, struck Jess Jonassen's third ball for four to reduce the equation to nine needed from three. That became five from one after a pair of quickly-scampered twos, but Sciver-Brunt was unable to find the boundary from the final ball.

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Tammy Beaumont also struck an impressive 60 at the top of the order for the hosts before being bowled by a beauty from Alana King (3-44), one of three wickets for the leg-spinner recalled to the Australian side for the game. Ashleigh Gardner also pitched in with 3-54.

England will look back ruefully on the final over of Australia's innings in particular, with Georgia Wareham smashing Lauren Bell for 26, including three sixes and two fours, to propel them up to what proved a match-winning score.

Heather Knight's side had otherwise done reasonably well to restrict Australia after winning the toss, despite two costly drops of Ellyse Perry who went on to score 91.

Perry was put down on 50 by Sarah Glenn, off her own bowling, and on 63 by Kate Cross at mid-off. Sophie Ecclestone also put down Gardner (33) when on just four as errors were again prominent in England's fielding display.

Although expensive late on, Bell (3-85) had given the hosts the perfect start, dismissing both Australia openers cheaply, Phoebe Litchfield (4) pinned lbw and captain Alyssa Healy (13) caught at short third.

Perry and Beth Mooney (33) rebuilt with a 61-run partnership, before the latter fell to Ecclestone, top-edging an attempted sweep to short fine leg.

Tahlia McGrath (5) came and went quickly - caught behind off Glenn (1-56) before Perry again enjoyed sizable stands with Gardner and Annabel Sutherland (50), who struck a maiden ODI fifty.

Ecclestone picked up Perry nine short of her hundred and added Sutherland later in the same over as England looked to be finishing the stronger until Wareham's crucial late cameo.

In reply, the scratchy Sophia Dunkley (13) shared in a 66-run opening partnership that Beaumont dominated and was eventually bowled by Wareham when looking to paddle one fine.

Spin was to be a constant threat throughout England's chase, with the captain Knight (12) next out lbw to King, albeit hugely aggrieved by the decision as she believed she laid some bat on it that went undetected by the umpire and UltraEdge on review.

Beaumont, soon after bringing up an 18th ODI fifty, was bowled by a beauty from King that pitched in line, turned away and kissed the top of her off stump, while Alice Capsey (2) somewhat gave her wicket away to the leg-spinner, holing out to deep mid-wicket.

It was then over to Gardner, who accounted for Danni Wyatt (8) and then Amy Jones (37) and Ecclestone (1) in the same over after a 57-run stand between Sciver-Brunt and the England wicketkeeper.

With the hosts reduced to 203-7, with 80 still required from the final 11.2 overs, it looked like England's chance was gone, only for Sciver-Brunt's sensational effort and a hugely-valuable, unbeaten 22 from Glenn to take them close.

But they ultimately left themselves a little too much to do and England's Ashes hopes were dashed by an agonising three-run defeat.

Knight: I thought we had it | 'It's the best women's series ever'

England captain Heather Knight:

"I loved the way Nat [Sciver-Brunt] batted, she was outstanding the way she played. I thought we had it in the end, credit to Australia.

"I was a bag of nerves in the dressing room. Two brilliant sides; it's the best women's series ever in my opinion.

"I thought the score was gettable but sometimes you've got to accept things and learn from it. Unfortunately we're on the wrong side of the result but there's still an ODI series to win and that would be a massive achievement against this team.

"We've played outstanding, Australia have played well as well and we are quite evenly-matched cricket teams. It's a hugely positive effort."

Healy: We pride ourselves in winning the key moments

Australia captain Alyssa Healy:

"Nat Sciver-Brunt played a pretty incredible innings. I thought she was going to take it away from us in the end. Our girls showed grit and determination.

"You talk about momentum in games and series, Wareham's innings actually swung it into our changing room at the break, and gave us a bit of a buzz. It turned crucial in the back end didn't it?

"We pride ourselves to win key moments. We came here to win the Ashes and we've retained them, it's exciting and huge congratulations to the group for getting it done."

Women's Ashes schedule (all games live on Sky Sports)

• Test match (Trent Bridge) - Australia won by 89 runs
• First T20 international (Edgbaston) - Australia won by four wickets
• Second T20 international (The Kia Oval) - England won by three runs
• Third T20 international (Lord's) - England won by five wickets
• First one-day international (Unique Stadium, Bristol) - England won by two wickets
• Second one-day international (The Ageas Bowl) - Australia win by three runs
• Third one-day international (Taunton) - Tuesday July 18 (1pm start)

Watch the third and final ODI of the multi-format Women's Ashes between England and Australia on Tuesday, live on Sky Sports Cricket from 12.30pm, ahead of the first ball at 1pm. Stream this summer's men's and women's Ashes series on NOW