Ten months after suffering a humiliating 40-6 loss to the Welsh that ultimately sent Australia crashing out of the Rugby World Cup, the Wallabies gained a small semblance of revenge on Saturday night.
An electrifying 68-metre solo try in the 66th minute to in-form fullback Tom Wright sealed victory in front of 35,945 fans at Allianz Stadium.
Powerhouse prop Taniela Tupou and winger Filipo Daugunu also crossed, while Jake Gordon celebrated his recall to the Test arena after missing Eddie Jones' World Cup squad with a dazzling man-of-the-match display.
Only seven Wallabies from that last-up, record-breaking loss to Wales survived as Schmidt rolled out a new-look team for his first Test as coach.
And he was rewarded with a gritty, if unspectacular performance from the Wallabies.
Tom Lynagh, the 21-year-old son of 1991 World Cup-winning legend Michael, earned a debut off the bench, directing the Wallabies home after being injected with 14 minutes remaining.
But the match was hardly a classic, with the ninth-ranked Australians emerging victorious after a bruising, error-laden arm-wrestle.Schmidt had inherited one of the most ill-disciplined sides in world rugby and would not have been impressed with serial offender James Slipper conceding a penalty in the opening two minutes.
Welsh flyhalf Ben Thomas slotted the goal to give the visitors first points of the match.
Recalled five-eighth Noah Lolesio, given first crack at playmaking and goalkicking duties under Schmidt, replied with two penalties of his own to put the Wallabies up 6-3.
It was 13-3 shortly after when Tupou finished off a series of pick-and-goes with Australia's opening try.
Pedantic French referee Pierre Brousset couldn't put his whistle away and eventually sent Wales prop Gareth Thomas to the sin bin for repeated infringements.
But the Wallabies were also down to 14 men when flanker Fraser McReight was yellow-carded trying to stop a Welsh driving maul.
The penalty try drew Wales back to within three points at halftime, despite the Wallabies enjoying a huge possession and territorial advantage and having to make a third of the amount of tackles as their opposition.
Scores were all locked up at 13-13 early in the second stanza before Dauguno popped up in the midfield, accelerated through the defence and raced 30 metres to slide over in the right-hand corner.
Hearts were in mouths when Welsh replacement James Botham crashed over from a maul, only for the television match official to rule an obstruction in the lead-up.
Lolesio bombed a try at the other end with a needless kick when the Wallabies had an overlap five metres out from the line.
Up 18-16, Schmidt substituted Lolesio for Lynagh, who became the 12th Australian to follow his father into the Test cauldron.
Fittingly, Lynagh had a hand in Wright's try, fielding a raking kick and sending the ball to his fullback, who burned the defence in a blazing run to end a horror sequence for the Wallabies in Sydney.
They had won only one of their previous 12 Tests in the NSW capital.
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