The honeymoon is over. The world's foremost rugby tournament resumes and expectations have rarely been raised so high. In fact, far from being afforded the traditional luxury of a wait-and-see approach from a quizzical Irish public, the Eddie O'Sullivan era will be expected to hit the ground running at Lansdowne Road tomorrow.

The IRFU's kingmakers will desperately hope so, too. Unoubtedly, it would be too simplistic to expect a reprise of the record 36-6 win in Cardiff last October, when Wales were a demorialised, under-strength shambles and incurred the customary wrath of their legion of legends as well as their demanding supporters.

With nine changes in personnel, and the strapping Scott Quinnell back in harness, they look an altogether stronger outfit this time round.

Now it's Ireland who look a little frayed at the edges, with injuries to four of the Cardiff line-up coming from the heavy Celtic and European load Munster and Leinster have had to carry this season.

Meantime, their Welsh counterparts were granted a reprieve during December, and Llanelli's Euro forays have given them a decided spring in their step.

Not that the backdrop has been remotely spring-like. A customary Irish weather forecast - some dry spells, some showers, more wind and whatever you're having yourself - would seem, on the surface so to speak, to favour Wales.

Their big pack looks well equipped for pick-and- go drives, or setting close-in targets (Quinnell uppermost amongst them presumably) to hone in on the David Humphreys channel.

However, they've also picked their tastiest back line in some time, and would presumably like to play to Iestyn Harris and those outside him as well.

The hard yards having been gained closer in, ditto Ireland. Getting the ball into the hands of Brian O'Driscoll, Denis Hickie and co in space has been part of the game plan ever since the Twickenham nadir two years ago and O'Sullivan has said that, in essence, Ireland won't change their spots now.

Before all that comes into play, the crunch markers will be laid down up front.

With the weather liable to increase the number of setpieces on a soft surface, the Irish scrum, seriously undone in this fixture two seasons ago, has to be a concern given the evidence of Munster's troubles there again last week, and parity would be a good day at the office.

Given any kind of a platform, Quinnell will rumble menacingly unless brought down low and early, and it could be that Simon Easterby's grafting qualities will be more suited to the needs of the day than Eric Miller's ball-carrying.

Even the nominated man-of-the-match against Stade, Paul O'Connell, was distinctly unhappy with the Munster lineout and, by filling the shoes of Keith Wood, no one will be under more pressure than Frankie Sheahan.

By comparison, Robin McBryde's 14 darts for Llanelli last week against Bath (Chris Wyatt being the prime target) were all on the money.

By and large, however, the lineout is usually a well-organised and varied source of attacking ball for both Munster and Ireland, though whether throws beyond the middle of either line will be much of an option has to be in doubt.

Indeed, the maul might be a better option, and here again this is a proven Munster virtue, less obviously a Welsh one. Though it's a big step up, even from winning a European Cup quarter-final in Paris, the unity and cohesion of the Munster pack may be particularly beneficial for this one and you sense O'Connell is well capable of rising to the challenge.

Geordan Murphy, too, can add a different kind of attacking dimension out wide to Shane Horgan, although the nature of the day mightn't demand it.

But most of all, while the ability of the four players called in stands up to those they've replaced, in all cases they bring less experience to the equation. Ireland look a little more unknown and unproven.

It could largely hinge on goalkicking and territorial kicking games of the outhalves, and by extension the discipline of both sides in the eyes of the Argentinian official. Stephen Jones is in a vein of form akin to Lord Humphreys of Ulster, with 16 out of 16 in his last two outings, but then again the Ginger Monster is not here to apply his curse, and this will be a windy Lansdowne, proven graveyard for kickers.

Backing up the Munster juggernaut, Peter Stringer (in many respects the key link for this team) looked positively refreshed rather than rusty a week ago. Indeed, lay-offs for some of the Munstermen have probably been a blessing, while Humpheys is having the season of his life.

O'Sullivan said yesterday he's been too busy to be nervous, though admits he will be tomorrow, and there's a palpable edge about Ireland. That's good though, remembering the costly lack of fear in this fixture two seasons ago.

Sometimes a change is as good as a rest. Remember Warren Gatland's first outing which nearly mugged an unsuspecting grand-slamming French? The planning has been detailed and the vibes from the Irish camp are good. Uncle Fester has stayed around for the week. They all want to part of a winning start to a new era.

Peter Clohessy's 50th cap ought to inspire crowd and team alike, though if 10,000 masks of Keith Wood prompted him to observe that it was the ugliest crowd he's ever seen, what will he make of this one?

But regardless of the backdrop, as one of them put it, if they're as good as they think they are they should win this one.