Dublin - An injury-ravaged Ireland became the first northern hemisphere side since England in 2003 to beat the three major southern hemisphere teams in a calendar year with a 27-24 win over Australia on Saturday.
Both sides scored three tries apiece while Paddy Jackson filled in for Jonathan Sexton brilliantly with a faultless kicking display in a thrilling game that saw the Australians come back from 17-0 to lead on the hour mark before the Irish found a second wind.
The defeat ends Australian hopes of emulating the legendary 1984 Wallabies side in completing the Grand Slam over the Home Nations.
Ireland started brightly with some incisive running, but having boldly kicked for the corner rather than take the three points, Aussie lock Rob Simmons stole back possession at the ensuing line-out.
Jackson at last decided to go for goal after refusing to do so on three occasions when David Pocock was penalised by French referee Jerome Garces and the Northern Irishman slotted it over for 3-0.
The Australians worked their way into a good position inside the Irish half for the first time in the 23rd minute but the good work was undone by experienced backrow forward Dean Mumm who aided by Simmons tip tackled Tadhg Furlong and was sin-binned.
A minute later and the Irish had taken full advantage as Simon Zebo's chip kick bounced kindly for Keith Earls and his superb offload to Iain Henderson saw the lock bundle over the line despite Will Genia bringing him down, before Jackson converted for 10-0.
Ireland, though, suffered further losses in personnel - they already had three key players out before the game started after a bruising battle with New Zealand last Saturday - as wing Andrew Trimble limped off on the half-hour mark, to be replaced by youngster Joey Carbery. Fullback Rob Kearney had already gone off with a head injury.
However, they made light of it as four minutes later they came up with their second try - this time the kick to the corner worked out - with a superb piece of individual brilliance and vision by Garry Ringrose seeing him give a jink of the hips and bamboozle Michael Hooper and Simmons before touching down.
Jackson converted for 17-0.
The Wallabies hit back and grabbed a try in the dying seconds of the half as Dane Haylett-Petty rounded off a superb passing move involving Hooper and Genia to touch down under the posts, with Foley converting for 17-7.
Incredibly the Irish had to make another change to their backline for the start of the second half as the influential Payne, who had been a doubt with a leg problem, failed to come out and reserve scrum-half Kieran Marmion had to come on as a wing with Earls moving to the centre.
Marmion's inexperience in the position was exposed immediately as he came in off the wing and Tevita Kuridrani went over in the corner to make it a try in each of their four Tests of the tour so far - Foley converting superbly to reduce the deficit to three points.
But an infraction by Pocock gave the Irish a welcome penalty and Jackson converted for 20-14.
However, the Aussies moved in front for the first time shortly before the hour mark as replacement Sefanaia Navalu burst through the tackle of Carbery and went in under the posts and Foley converted for 21-20.
Foley put the Wallabies further ahead with a penalty in front of the posts, but the Irish somehow conjured up another try as Zebo delivered to Earls who crossed in the corner for his 19th try in the green jersey.
Jackson converted for 27-24 and somehow they held on for a deserved victory.
15 Rob Kearney, 14 Andrew Trimble, 13 Jared Payne, 12 Garry Ringrose, 11 Keith Earls, 10 Paddy Jackson, 9 Conor Murray, 8 Jamie Heaslip, 7 Josh van der Flier, 6 CJ Stander, 5 Devin Toner, 4 Iain Henderson, 3 Tadhg Furlong, 2 Rory Best (captain), 1 Jack McGrath
Substitutes: 16 Sean Cronin, 17 Cian Healy, 18 Finlay Bealham, 19 Ultan Dillane, 20 Peter O'Mahony, 21 Kieran Marmion, 22 Joey Carbery, 23 Simon Zebo
15 Israel Folau 14 Dane Haylett-Petty, 13 Tevita Kuridrani, 12 Reece Hodge, 11 Henry Speight, 10 Bernard Foley, 9 Will Genia, 8 David Pocock, 7 Michael Hooper, 6 Dean Mumm, 5 Rob Simmons, 4 Rory Arnold, 3 Sekope Kepu, 2 Stephen Moore (captain), 1 Scott Sio
Substitutes: 16 Tolu Latu, 17 James Slipper, 18 Allan Alaalatoa, 19 Kane Douglas, 20 Sean McMahon, 21 Nick Phipps, 22 Quade Cooper, 23 Sefanaia Naivalu