The switch in mood in and around Ireland has been unmistakable this week.
Last week, the Irish were fortifying the ramparts, bracing the gates, and manning battle stations in anticipation of a barrage from New Zealand. The All Blacks were in a take-no-prisoners mood after being caught with their pants down in Chicago by the Irish at the beginning of the month.
The Kiwis left Dublin with the win they demanded last weekend, and Australia rolled into town.
Article continues below ...
And it was like old friends came home. Wallabies coach Michael Cheika lived for five years in Dublin, transforming Leinster into a European club champion. Skills coach Mick Byrne helped Leinster in the 2002-03 season. Lock Kane Douglas lasted less than a season at Leinster before he was recalled home last year for the Rugby World Cup, but left behind good memories, too.
Cheika said he's been seeing Irish friends in down time, and suggested if he can't catch them all up, then ''I can always come back for holidays.''
There's little of the tension in the air like last week also because the Wallabies, unlike the All Blacks, haven't lorded over the Irish for 111 years.
The Irish record against Australia is their best against the southern hemisphere's Big Three.
Ireland has beaten the Wallabies 10 times in 32 contests, including the last one in 2014, when Cheika had been Wallabies coach for less than a month. The Irish bolted to 17-0, and Australia fought back to tie the game at 17, 20 and 23. The Irish won 26-23.
Cheika's powers of persuasion have lifted the Wallabies again from the depths of the Rugby Championship to successive wins over Wales (32-8), Scotland (23-22), and France (25-23). They are halfway to a Grand Slam of the home unions.
''It would be very enjoyable for me (to win in Dublin), I've spent so many good years here,'' he said. ''I was very disappointed to lose here in 2014 but that's not what it's really about at the end of the day.
''We've come here with a third of a new squad from when we came to Europe last year before the World Cup. A lot of those guys haven't played in Europe before so the atmosphere of playing in Lansdowne Road and that challenge … it's really difficult to win in Europe. For our guys who haven't had those experiences, it will be a big game.''
For the match, Israel Folau, Sekope Kepu, Rory Arnold, Reece Hodge, and Dane Haylett-Petty are back after being rested against France, and Dean Mumm and Rob Simmons have been plugged into the pack to contest Irish throw-ins.
Ireland has had to come down from the high of playing New Zealand, patch up bumps and bruises, and prepare to rise to the occasion again. The wonder is whether the team can after putting in a huge workload to compete with the All Blacks twice in the last three weekends.
If any extra motivation was needed, there was captain and hooker Rory Best's 100th cap to celebrate. He's the fifth Irishman to reach the milestone, after Brian O'Driscoll, Ronan O'Gara, Paul O'Connell, and John Hayes.
''You're playing Australia, it's not time for rest,'' prop Jack McGrath said.
''It's been a fairly hectic four weeks. But it's been exciting and, for us as a squad and a country, we've stepped forward in the rugby world. It's good. It's a good place to be.''