It is sweaty palms time already. The Aviva Stadium could be the rock on which Leinster's season perishes in the Magners League on Saturday evening.
The facts are straightforward: Leinster have lost three out of four in the Magners League, have conceded more points than everyone except the Dragons and Aironi, have leaked as many tries as they have scored (nine) and trail leaders Munster by a yawning 12 points.
Leinster scrum-half Isaac Boss made a rallying cry: "We're going to have to be very physical for the first 20-30 odd minutes and right through the 80 minutes.
"We've got to get body on body and everyone flying into things. It is going to be a war of attrition and, hopefully, we can come out on top," he said.
"We've leaked tries. We've made a lot of errors. We've got to worry about ourselves, tighten up our defence. As individuals, we've got to make sure we look after our own shop first."
It would be difficult to envisage how Joe Schmidt's side could rebound from a soul-destroying defeat to Munster to challenge for what is their bread-and-butter in the newly arranged Four Nations competition.
On the back of this, it would be even more unlikely for them to trump French club Racing-Metro, joint head of the French Top-14 after eight rounds, at The RDS on Saturday week.
Thereafter, heavy spending Saracens, who have started the Guinness Premiership brightly with three wins from four, will want to show their mettle at their temporary home of Wembley the following Saturday.
"We have to take one step at a time. We can't look three games ahead. We've lost the last couple. We'll look at this one and worry about the other two after that," said Boss.
It is a three-match sequence that could break or repair Leinster's season. First and foremost, they will have to subdue a Munster side that has shrugged off the considerable loss of Paul O'Connell and Jerry Flannery to smack Edinburgh (16-13) and Glasgow Warriors (43-29) away from home as part of their four-match winning start in the League.
"There is no doubt they've done well away from home this season. The first match in The Aviva neutralises it for them, if anything. It gives them something to look forward to as well," continued Boss.
"They've started very strongly. It doesn't seem to matter who is playing there at the moment. We've had a couple of opportunities we haven't taken that could have turned things around for us. They are the opportunities that they are taking."
The former Waikato server provider is involved in a tussle with Eoin Reddan for game time. The choice seems clear and distinctive.
Should Schmidt go with Boss, the equivalent of a ninth forward, or the more cerebral skills of Reddan? "Everyone wants to start. I have been pushing hard for the last few weeks. We will see what happens. I will take nothing for granted," he insisted.
Right now, Leinster need aggression and intent on the gain line. Schmidt wants to see the desire to make that conclusive tackle and carry beyond the gain line.
It is all about momentum and Leinster have precious little of it.