TOKYO -- It was the one of the games of the tournament four years ago.
Having both dispatched of England, condemning the hosts to a miserable pool-stage exit, Wales and Australia met at Twickenham in a game that would decide Pool A and, more importantly, end up on the opposite side of the knockout draw to the All Blacks.
What transpired over the next 80 minutes at the home of English rugby would be one of the most unforgettable tryless games on record, and a match that seemed to fortify belief in Michael Cheika's Wallabies squad.
Not because of the way they had attacked or executed with any great skill - no this was a triumph of defence and sheer determination from Australia, that Wales would not breach their line.
Even when the Wallabies went down to 13 men for seven arduous minutes.
"I got yellow-carded around the 50th minute and I didn't come back on, so I was pretty disappointed," Wallabies scrum-half that night, Will Genia, recalled with a chuckle earlier this week. "But just an immense defensive effort; I remember one tackle that Benny McCalman made where he held George North, he might have been over the line, and then a couple of plays later they had six-on-three and we ended up snuffing it out and getting a penalty.
"So just a big, big defensive effort and coming back to what we were saying before, just patience with the ball and without the ball. We speak about it being a strength for them but it's going to be something we're going to have to have come Sunday as well."
McCalman's tackle is remembered fondly across that crop of Wallabies and featured prominently in tributes when it was revealed the man known as "Big Dog" had slipped quietly into retirement by returning to the family farm at Warren in drought-stricken NSW.
It's no easy feat bringing down a charging George North at the best of times, let alone when you are the last-line of defence and the tryline beckons.
The former Force back-rower came off the bench that night at the height of Cheika's "finishers" period, a mantra that was supposed to give extra responsibility to those players named among the replacements instead of being just that: replacements.
And they certainly fulfilled their role that afternoon at Twickenham.
Fast forward four years, and the two sides, who are again evenly matched, face off this Sunday afternoon at Tokyo Stadium. The prize on offer, is remarkably similar and comes with the added caveat of avoiding an imposing looking England side who on Thursday night swept aside the United States with many frontline stars absent.
Win Sunday evening's match and a quarterfinal with France likely beckons, followed by a semifinal showdown with either Ireland or South Africa. It is seemingly a far more serene passage to a berth in the final than having to go through both England and the All Blacks.
Sunday's Test is again a massive showdown.
And Cheika knows as much, reverting to a vastly-more experienced backline after some players had failed to hit the ground running against Fiji last week. In come veteran halves duo Will Genia and Bernard Foley while Dane Haylett-Petty replaces Kurtley Beale at fullback and Adam Ashley-Cooper, at 35 years of age, is the man to fill the suspended Reece Hodge's jersey.
Whether the circus that has evolved around the Hodge citing process and subsequent opinion-splitting debate around his tackle have been a distraction for the Wallabies, will be evident right from the opening whistle. But in no way can they afford to start like they did against Fiji.
Wales, meanwhile, are riding high. They are the reigning Six Nations champions and, vitally, ended a long run of woe against the Wallabies in a grinding 9-6 win at the Principality Stadium in Cardiff last year.
They, too, are flush with experience even without the retired Sam Warburton and boast a twin breakdown threat of their own in Justin Tipuric and Josh Navidi. This tournament also represents Warren Gatland's Wales swansong, so the motivation is strong to send the Kiwi home on the best possible note.
"We can take a little bit from that game [Cardiff win]," Wales lock Jake Ball said Thursday. "But it's all on the day, controlling the emotions. I think a lot of the teams in this tournament on their day they can beat each other.
"It's a massive game and that's what all us players thrive on really. I'm just excited to get out there. Australia are a dangerous team, play a lot of running rugby, and have got attacking threats right across the board."
And you wouldn't rule out any drama, the kind of which we saw four years ago, from happening again. Even during Australia's long period of dominance over Wales, when Gatland's record against all southern hemisphere nations - as coach of Wales - was particularly unflattering, there was never too much between these sides.
Given the potential prize on offer and the knowledge that no team has ever lost a pool match and gone on to win the World Cup, it promises to be an anxious evening at Tokyo Stadium on Sunday.
And it may just be that Australia need another "Big Dog" defensive effort to get it done, preferably this time by keeping all 15 players on the field.