Australia recovered from conceding a first-minute try and twice falling 10 points behind to record their ninth successive win over Wales with a dramatic 30-26 victory at Cardiff's Millennium Stadium on Saturday.
The Wallabies scored three tries to two from Wales wing George North, with Australia centre Christian Leali'ifano, who crossed the Welsh line, contributing 20 points in all.
This success for Ewen McKenzie's men was all the more significant given Australia and Wales have been drawn in the same World Cup 'group of death' as 2015 hosts England.
And the Wallabies' tour-ending triumph also meant they'd won four Tests in a row for the first time since the opening matches of former coach Robbie Deans's reign in 2008.
Australia fly-half Quade Cooper marked his 50th Test with several moments of superb passing skill as the Wallabies fought back to lead 17-16 at the end of a breathless first half.
"As a team we're very relieved," man-of-the-match Cooper told the BBC. "We've started to put things together as a team but Wales kept coming back at us."
For Six Nations champions Wales this loss extended their poor run against the southern hemisphere giants of New Zealand, South Africa and Australia to just one win in 23 Tests.
And that was despite coach Warren Gatland's starting XV containing nine members of the victorious British and Irish Lions squad the New Zealander guided to a 2-1 series win in Australia in July -- but not injured centres Jonathan Davies and Jamie Roberts.
"From our point of view I think we've been here a few too many times," a disappointed North said.
In a match where the closed retractable roof made conditions ideal for running rugby, Wales made a stunning start after a slicing run by Australia full-back Israel Folau was ended only by last-ditch cover defence.
Welsh lock Alun Wyn Jones won turnover ball and fellow Lions star North sprinted clear.
North kicked ahead and, with Adam Ashley-Cooper failing to deal with the loose ball, regathered for a try.
Leigh Halfpenny, man of the series for the Lions in Australia, landed the tough conversion and kicked a penalty to leave Wales 10-0 ahead before Leali'ifano exchanged penalties with the full-back.
But there was barely time to draw breath in an end-to-end match before Australia hit back with a superbly-crafted score in the 18th minute.
Flanker Michael Hooper won a turnover before Cooper's back of the hand pass found Joe Tomane, with the wing's precise inside ball to Leali'ifano sending the centre in for a well-worked try, which he converted.
Then, to the collective astonishment of a capacity crowd, Halfpenny saw a penalty kick come back off the left post.
But fly-half Dan Biggar kicked Wales into a 16-10 lead on the half hour after Australia lock James Horwill left his hands in a ruck.
And Australia, in a first half where there wasn't a single scrum, turned round with a one-point lead thanks to a try scored soon after Biggar was sin-binned for holding on at the tackle.
Folau, missed by Mike Phillips when the Wales scrum-half was too high with his attempted tackle, crossed from close range, despite thumping tackles by North on Ashley-Cooper and hooker Richard Hibbard on Australia captain Ben Mowen in the build-up.
And Australia had another try in the 48th minute when Tomane plucked the ball off the ground following a poor pass from Folau.
English referee Wayne Barnes decided the final ball hadn't gone forward because Folau's hands went back in the act of passing -- a decision jeered by a crowd of more than 67,000.
Leali'ifano converted and added a penalty to leave Australia 30-16 in front.
But this time it was Wales's turn to bounce back with North leaving srum-half Will Genia in his wake for a 58th minute try.
Biggar converted before a penalty from his replacement, Rhys Priestland, cut the Wallabies' lead to four points.
Australia had to play the final few minutes a man down after Cooper was yellow-carded for tackling Scott Williams without the ball but they held on.