Today's clash at the RDS is unlikely to be the defining moment for Leinster's challenge in the Heineken Cup. It is difficult to imagine that one of the great teams in the history of this competition will not be able to deliver a bonus-point win at their Ballsbridge home. The real challenge will come in Exeter next week.
However, this team know that they can only take one match at a time and that other games in other groups are outside their control.
For the first time in this season's competition, Leinster can select something close to their first- choice XV. Brian O'Driscoll (bench), Rob Kearney, Isa Nacewa, Sean O'Brien and Luke Fitzgerald are all selected, but not necessarily fully recovered or, in some cases, match fit.
As Munster have demonstrated, the loss of an outstanding player and leader like Paul O'Connell has seriously damaged their performances. Imagine, then, what it must be like for Leinster as Joe Schmidt juggled with a lengthy injury list, as well as adhering to the IRFU's player welfare system.
Thus, if the coach gets his team to the last eight, it could be considered the finest achievement of his career.
However, injury list or no, Leinster have looked a tired squad this season. So far, they have scored just three tries in the entire competition. Their below-par performances, while disappointing for coaches and players, are not all that surprising, however. The physical and mental demands of this tournament are immense and Leinster's return of three Heineken Cups from the last four seasons is remarkable. But something had to give as Schmidt looked to maintain Leinster's hunger for success, while managing an injury-ravaged squad.
The Scarlets have been in poor form in the Pro12 League of late. They have dropped from second place to fifth in the table, have conceded 59 points in their last two matches and have yet to win a match in this season's Heineken Cup. Leinster, with a full-strength side, should have enough firepower to secure the bonus point they need.
Even with a fully-fit squad, the Scarlets would struggle to get anything out of this fixture, but they are missing two of their best players in wing George North and out-half Rhys Priestland through injury. North had to be taken off against Ulster last weekend with a neck injury, but looks set to recover in time for Wales' Six Nations campaign, while Priestland is out for six months.
Leinster must implement a high-tempo game plan from the first few minutes; quick ball to the backs with support lines from the back-row. Ulster showed last weekend when scoring five tries that Scarlets out-half Aled Thomas is vulnerable in defence. If O'Brien and company in the back-row attack his channel at pace, gaps will open.
For those concerned about the IRFU's extraordinary decision to recruit Michael Bent from New Zealand without having seen him play, the last few weeks have been worrying. The Kiwi came with the usual health warning, "this player can play on both sides of the scrum," which is usually shorthand for "he cannot play on either side." His latest scrummaging performances have been substandard, which, coupled with the backward steps taken by Mike Ross, leave Leinster and Ireland in a precarious position over the next couple of months.
Irish second-rows must be pretty peeved that the blame is now being levelled at their efforts behind the front-row. Clearly the IRFU advertisement in New Zealand read: 'Wanted: one prop forward with Irish qualifications, scrummaging experience not required."
Many of the players today will have one eye on February 2 and the opening of the Six Nations championship. The physical toll on the combatants in this sport is now almost beyond human endurance.
One has to assume that, behind closed doors, the medical advisers to the International Rugby Board must be trying to create a game that will not lead to the raft of class action suits that currently exercise the minds of the organisers of the NFL. Rugby players, however well-paid, deserve the expectation of a pain-free middle-age.
While much has been made of the quality of young players coming through in Leinster and Munster, the absence of O'Connell at Munster and O'Driscoll and Kearney at Leinster has shown that much still rests on the shoulders of senior players. Munster have looked leaderless without O'Connell's influence and Leinster lack organisation in defence and a cutting-edge out wide without O'Driscoll's vision and experience.
The next two years will bring an end to the so-called 'golden generation' of players and it remains to be seen whether the current crop coming through can take on the mantle. As it stands, we could be faced with a Heineken Cup quarter-final stage without Leinster and Munster and that must be worrying.
The good news is that the two provinces will most likely be still be the shake-up next weekend.