|Third Test: Australia v Ireland|
|Australia (9) 16|
|Try: Koroibete Con: Foley Pens: Foley 3|
|Ireland (12) 20|
|Try: Stander Pens: Sexton 5|
Ireland resisted a sustained second-half assault to earn a first series victory in Australia for 39 years.
The Six Nations Grand Slam champions needed the boot of Johnny Sexton to steer them through a scrappy but compelling contest in Sydney.
CJ Stander's try at the start of the second half was cancelled out by an excellent score by Marika Koroibete.
The Wallabies scented a win but the Irish defence held firm before Sexton kicked a late insurance penalty.
The tourists found themselves under relentless pressure as Australia sought to harness the momentum of Koroibete's try.
There was still time after Sexton's fifth and final penalty for the home side to stage one final, desperate attack but Bernard Foley's wayward pass missed its target and rolled out of play just as the clock turned red.
Wallabies learn Melbourne lessons
A major factor in Ireland's win in Melbourne to level the series had been their ability to negate the influence of Australia's key players.
Wallabies coach Michael Cheika had clearly learnt from that defeat as number eight David Pocock and full-back Israel Folau were both to the fore in the opening quarter after their captain Michael Hooper suffered an early hamstring injury.
Folau won the ball from the opening kick-off and his aerial contest with Peter O'Mahony was a feature of the game up to the 30th minute when the Ireland captain was carted off injured and the Wallabies full-back was shown a yellow card for taking the flanker out in the air.
The sides were level on six points and 14 players apiece at that point after Sexton and Foley had traded penalties and Jacob Stockdale had also been sent to the sin bin for leading with his forearm.
The Ireland fly-half pushed his side back ahead with a 35th minute penalty.
Australia thought they had levelled before the break when Foley punished a Conor Murray offside but the hosts conceded a penalty from the restart - much to the annoyance of Chieka - and Ireland led by three at the interval.
Stander turns pressure to points
Ireland had dominated the territory and possession stats in the opening half but, not for the first time in the series, they had struggled to convert that pressure into scores.
They began the second half determined to correct their profligacy and immediately set up camp in the Australian 22 after a clever kick by Sexton.
The Irish pack cranked up their line-out maul and were held up at the first attempt before Stander was at the tail of a second driving wedge that powered over the line.
Sexton missed the conversion, which left Ireland with a precarious eight-point lead.
Koroibete sparks fight back
In what was the final game of a gruelling 11-match season, Ireland began to tire as the final quarter approached and the Wallabies sensed their chance as Foley turned down two kickable penalty chances to kick into the corner instead.
The first attack produced a chance for Folau when the full-back found some space on the blind-side but the final pass went over his head.
But there was no mistake at the second time of asking as the Irish defence was sucked infield and Foley's perfectly-weighted kick bounced up into the path of Koroibete, who dragged Sexton over the line with him.
The conversion meant it was just a one-point game with more than 20 minutes remaining, and Australia attacked in waves against a tiring Irish defence.
Robbie Henshaw was penalised for a high tackle but Foley's penalty attempt drifted across the face of the posts and substitute scrum-half Joe Powell's pass was knocked-on by Samu Kerevi when a try seemed inevitable.
Ireland countered with Sexton's penalty in the 78th minute on a rare foray into the opposition half before the Wallabies final, desperate attack fizzled out as the hooter sounded.
What they said
Ireland head coach Joe Schmidt, speaking to Sky Sports: "I think a heck of a lot of it tonight was about character. Maybe we should have got a little bit more out of that first half.
"The Wallabies then came back and they came back in waves, but I think credit to Jordan Larmour, Jordi Murphy, Tadhg Beirne for coming into a real furnace and to come out on the other side. I hope that furnace helps them become the diamonds that we need.
"The provinces do a great job looking after the players and making sure they have enough juice in the tank. I don't think we could play again next week, I think all that juice is gone."
Ireland try scorer CJ Stander speaking on Sky Sports: "We knew it was going to be a cup final for us coming down here, especially as it was the last game of the season so I think we just got out there and gave it 100%.
"We knew Australia would attack us from minute one. We pride ourselves on our defence. They came at us wave after wave for the last 20 minutes and we stood up and I am immensely proud of the guys."
Australia number eight David Pocock speaking on Sky Sports: "It was a great battle. Every week you were trying to analyse their game and see what weaknesses of ours they were going to try to target.
"But credit to them, maybe their game management was a little better across the series."
How they lined up
Australia: Folau; Haylett-Petty, Kerevi, Beale, Koroibete; Foley, Phipps, Sio, Paenga-Amosa, Kepu, Rodda, Coleman, Tui, Hooper, Pocock.
Replacements: Latu, Robertson, Tupou, Simmons, Hanigan, Samu, Powell, Hodge.
Ireland: R Kearney; Earls, Henshaw, Aki, Stockdale; Sexton, Murray; J McGrath, N Scannell, Furlong, James Ryan, Toner, Stander, O'Mahony, Conan.
Replacements: R Herring, Healy, John Ryan, Beirne, Murphy, Marmion, Byrne, Larmour.
Referee: Pascal Gauzere (France)