If there was ever a time to embrace the underdog tag, it's now. A quarter-final against New Zealand will require what we've all been waiting for: a big-time performance from this Irish team to do what they never have and reach the final four.
Despite recent form, they need to conjure up from somewhere the performance of their rugby year. Expectations may be low, but there's another way of looking at it: there is no pressure on them. The All Blacks have shown real form and have the momentum of a juggernaut, while questions have been asked about Ireland: their form; their game plan being figured out; handling errors; fatigue; the struggle with humidity.
But what is important to the players is they know they can beat New Zealand: they've won two out of last three meetings. In terms of pressure, their form actually puts them in a nice position as few will really expect them to win, even though deep down they'll know they have the capability of doing so.
Samoa, of course, present a whole different ball game to New Zealand, but Saturday was an indication that Ireland's form is coming back just in time. Even though we beat Russia comfortably it wasn't a confident or clinical performance, but this was different - a performance that should rid the camp of some self-doubt.
The players looked less nervous and the handling errors appeared to be resolved. The 14-man situation didn't help but it made Ireland focus and they adapted by putting Conor Murray in the line and not committing numbers to the defensive breakdown.
There were also subtle changes to Ireland's attack. Forwards attacked slightly wider channels, getting out to the third defender rather than attacking very narrowly as in previous games.
But this subtly wider attacking shape depends on Murray and Sexton orchestrating it because when they left the field, we went narrower with pick-and-go and one-out runners. With the half-back change we seemed to revert to type and it showed our reliance on our front liners.
It was promising to see Murray return to form. He had been visibly struggling for a number of months, but his pass to Larmour for the try was top-class and we will need him at his very, very best to create history on Saturday.
Now that Joe Schmidt is not faced with the injury problems that blighted Ireland's chances in 2015, he'll have a much wider array of ammo to choose from.
Robbie Henshaw looked rusty on Saturday, which is understandable given he hadn't played in this World Cup, but Bundee Aki's red will mean that Schmidt will likely go for a centre partnership of Henshaw and Ringrose.
Ringrose has been playing well and is capable of producing big-game moments which we will need on Saturday. Schmidt will back Henshaw to pick up his form for the quarter-final.
The big question for Schmidt this week is whether he goes off recent form or sticks with his usual, the tried and tested. I would be disappointed not to see Tadhg Beirne start ahead of Peter O'Mahony but Joe will probably go with O'Mahony, backing him to get back to his best form.
Tadhg Furlong appears to be back on song, as does Best, who I was a critic of before the World Cup due to recent form and his playing age. But the 37-year-old is showing us all why he is the captain, playing as if every game could be his last.
I'm interested to see who Schmidt picks at full-back and right now it's hard to tell. It will likely come down to training this week.
As for their rivals: what more can be said about New Zealand?
Where they are so dangerous is when they transition from defence to attack or pick up turnover ball. They don't necessarily need to win the possession stats to take their opportunities and kill you on the scoreboard.
They're a team with an ability to make something out of nothing which means Ireland will have to keep the error count low and have an intelligent kicking game that doesn't give them an opportunity to transition. The only way we can win this game is if we force New Zealand to work for their scores and not gift them opportunities through errors.
New Zealand have two play-makers in Beauden Barrett and Richie Mo'unga who will look to set their attack in motion. With dangerous wingers like Sevu Reece and George Bridge, our defence will need to be alert to the dual threat and be conscientious of the threat out wide.
It's the quarter-final no one wanted, the one most believe will be Ireland's Armageddon.
But ever since Saturday, we have a lot more reason to believe in the upset.