Ireland backed up their win over South Africa two weeks ago as they held off a determined Australia fight-back to edge victory in a thrilling game in Dublin.
Joe Schmidt’s Irish looked in control after Simon Zebo’s try and Tommy Bowe’s breakaway score helped them lead 17-0.
However, the strong-running Wallabies fought back to lead after two Nick Phipps tries and a Bernard Foley score.
Sexton’s penalty levelled before the break and his two second-half penalties proved enough for the Irish.
The victory was a big turnaround from their 32-15 walloping by the Wallabies 12 months ago and was further indication of how far they have come under New Zealander Schmidt.
After Saturday’s game, it was revealed that Schmidt, 49, had been suffering from suspected appendicitis and had gone to hospital for tests.
The victory completed a clean sweep of November triumphs for the first time since 2006, with the Irish having leapfrogged the Australians into third place in the world rankings after their wins over Springboks and Georgia.
Australia coach Michael Cheika’s knowledge of the Irish players had dominated the build-up to the game but the home side produced the early fire as they stormed into a 17-0 lead within 17 minutes.
Sexton edged Ireland ahead in the sixth, although the Irish fly-half was off target four minutes later after Australian prop James Slipper had been fortunate to avoid a yellow card for a high tackle on Rob Kearney.
Ireland’s first try came two minutes later as Sexton’s kick – after Rory Best had dispossessed Luke Jones near halfway – bounced perfectly for Zebo to score.
After Sexton’s successful conversion, the Australians threatened an immediate response through Foley and Kuridrani, but a seemingly outnumbered Bowe ended the attack by intercepting Phipps’s laboured pass and running from deep in his own 22 to score at the other end.
Sexton’s conversion increased the lead to 17 points as Irish found themselves in a similar position to the one they had carved out against New Zealand 12 months ago.
But the visitors hit back within a minute as Phipps atoned for his mistake by running from his own half to score after Zebo’s ambitious off-load had been intercepted by Aussie debutant Henry Speight.
As the Aussies opted to run the ball at every opportunity, Foley touched down again five minutes later, with the television match official deeming Phipps’s pass to have been level.
With Foley missing the conversion, Ireland’s lead was 17-12. But Australia were on terms by the half hour after more sensational running and off-loading from Matt Toomua, with Foley setting up Phipps to score his second try.
Foley’s struggles with the boot continued as he missed the straightforward conversion but more magnificent work from Toomua set up another simple kicking chance for the fly-half in the 37th minute.
This time he took advantage but Sexton’s penalty in injury-time brought the sides level.
The Aussies appeared to have the momentum as the players headed into the dressing rooms but Ireland were back in the lead four minutes after the resumption as Zebo’s dancing feet led to a breakdown infringement by the Wallabies, with Sexton punishing the offence.
But the visitors were back on terms with four minutes as Foley profited from an Irish scrum which was showing signs of starting to wilt.
Yet the Irish were succeeding in making the game a less open contest and they regained the lead on 64 minutes through another Sexton penalty after Kearney had struck an upright with an amazing drop-goal attempt from 50 metres.
With Kurtley Beale and Quade Cooper introduced, Australia produced inevitable late pressure but the Irish held on to complete their run of autumn wins.
Ireland (20) 26
Tries: Zebo, Bowe Cons: Sexton 2 Pens: Sexton 4
Australia (20) 23
Tries: Phipps 2, Foley Cons: Foley Pens: Foley 2
TEAMS
Ireland: Rob Kearney; Tommy Bowe, Robbie Henshaw, Gordon D’Arcy, Simon Zebo; Jonathan Sexton, Conor Murray; Jack McGrath, Rory Best, Mike Ross: Devin Toner, Paul O’Connell (capt); Peter O’Mahony, Rhys Ruddock, Jamie Heaslip.
Replacements: Sean Cronin for Best 68 mins, Dave Foley for Toner 61, Eoin Reddan for Murray 72, Ian Madigan for D’Arcy 59, Felix Jones for Kearney 78
Not used: Dave Kilcoyne, Rodney Ah You, Tommy O’Donnell
Australia: Israel Folau; Adam Ashley-Cooper, Tevenia Kuridrani, Matt Toomua, Henry Speight; Bernard Foley, Nick Phipps; James Slipper, Saia Fainga’a, Sekope Kepu; Sam Carter, Rob Simmons; Luke Jones, Michael Hooper (capt), Ben McCalman.
Replacements: James Hanson for Fainga’a 69, Benn Robinson for Slipper 75, Tetera Faulkner for Kepu 69, Will Skelton for Carter 72, Jake Schatz for Jones 54, Will Genia for Phipps 69, Quade Cooper for Foley 65, Kurtley Beale for Kuridrani 46.
Referee: Glen Jackson (New Zealand)
