It is the big one. Ireland versus England in Dublin. The opportunity to make the rest of the civilised world smile. No matter how much the previous week has taken out of you and how tired you feel there is no problem getting up for one of the highlights of an international rugby career.
The Irish players have to concentrate on what they did well against Wales.
There was a real energy and ambition about Ireland's first half performance.
Given that the pack was expected to have had slight lineout superiority it may have suited more to kick the ball off the park.
Instead, the fact that Ireland kept the ball in hand so much was a statement of confidence and self-belief.
Every now and again when it was needed we saw the kicking game that is now part of Jonathan Sexton's armoury.
For all that Declan Kidney has his critics, he had his boys firing on all cylinders and playing as a team.
Despite the mania of the second half, Ireland's reaction to Wales' final thrust in the last few minutes was admirable.
Wales struggled to get out of their own 22 as the Irish defence stayed controlled, composed and resolute.
It was this last act of defiance that will reinforce the team's confidence going into the match against England.
It will be a totally different style of game – much cagier, more tactical and attritional – a tighter game over the 80 minutes with smaller margins.
Therefore, for me, the biggest single factor will be discipline.
The precision of both Sexton and Farrell means that neither side can afford profligacy. Whoever comes out on the right side of the penalty count will win the game.