The back-to-back pre-Christmas arm wrestles against a re-configured Northampton has ramifications.
Christmas past and Christmas present are Leinster’s current considerations. Last year, coach Joe Schmidt struggled for the two games against Clermont and the festive period became one of dashed hopes.
The European journey was badly holed by the coming together of mounting injuries and a strong French side.
A 15-12 defeat in Stade Marcel Michelin and losing 21-28 in front of 50,000 in Aviva left Leinster in a hopeless chase.
The fit again Leo Cullen may be making a charge that is too late for a secondrow start this week given the international work of Devin Toner, who started against the All Blacks, and Mike McCarthy, who was on the bench. But his voice will be heard around the camp. What he will be saying is ‘remember last year and forget the European final of 2011’.
Cullen’s two seasons with Leicester would have brought him into contact with Northampton more than occasionally but it’s a changed side to the one that suffered Leinster’s famed second-half revival in the 2011 final.
The scar tissue from that is less debilitating, more of a reminder.
"You look at some of the players they have brought in since then, like the Pisi brothers, for example, who are very talented rugby players and they added different dimensions to their game," says Cullen.
Suspended
"Obviously, I know one of them [Samoan international George, for a tip tackle on Tommy Bowe] will be suspended. If that's the case, [Luther]Burrell, has taken the Jimmy Downey role that was there before.
"He is strong, physical, gets the team going forward . . . like George North, who is probably one of the outstanding wingers in world rugby at the moment.
“So if you have got quality like that you know they have got exciting players across the board. There are very strong ball-carriers and if you let them play they are a dangerous team.”
It's almost as if Cullen has listened in to a Jim Mallinder [Saints coach] assessment of Leinster.
Then again his opinion next year could be sought as a coach as his contract expires and respect for him in the different role grows with him. On that possible change he remains reticent.
“I want to get back playing at the moment,” he suggests reasonably.
“We enter into a pretty hectic phase over this December-January period and then we can reassess after that. There will be more time for me to look at the options then”.
Cullen had been injured until last weekend but played a full role, apart from a stay in the sin bin, in Leinster’s win over Scarlets. Despite their strength in personnel, his sense is Leinster need to be cautious in the way they proceed.
"Going back over a number of years, Leinster were very guilty of crumbling around January time. You had a lot of poor results at the tail end of the Heineken Cup [pool]," he says.
Critical time of the year
"These back-to-back games, especially for ourselves and Northampton, could be crucial for deciding who comes out of this group. It is a critical time of the year where there are other distractions going on. But, it is important we stay focused."
Not unlike flanker Seán O'Brien Northampton have in-your-face players like Courtney Lawes and Samu Manoa. Abrasive and damaging in set- pieces and defence, their willingness to take it to Leinster will only be heightened by the close-feel, old-school ground at Franklin's Gardens.
They have also had a successful run since the season began and have lost one match and drawn one from nine and sit second in the Premiership table behind Saracens. They have also scored more tries (27) and jointly conceded the least (11) in the competition.
“Samu Manoa, he is very abrasive, very strong ball-carrier, very strong defence. They’ve got plenty of quality there. Set-piece with these guys is always a massive challenge,” says Cullen.
“When they play at Franklin’s Gardens, they’ll want to take us on physically. Courtney Lawes is a huge part of that because of the physically imposing guy that he is. We know we need to be on our mettle whoever is playing this weekend.”
There is nothing to be won over the next two weeks, but it could all be lost.