True, we're being slightly mischievous because even if Ireland do lose today, O'Sullivan appears to be secure and it would probably take a catastrophic hat trick of defeats against Wales, Scotland and England to change that. Not that it should, but we've already been through the reasons why O'Sullivan should make way and as the coach himself is keen to say, it is what it is. It's not something that's going to be sorted one way or the other this afternoon, although it may have an important contribution to the whole 'should he stay or should he go' debate.

Mischief aside, there's little doubt this one's a seasondefining fixture for both sides, the third weekend in this tournament always is. A victory and Ireland can eye a potential championship and Triple Crown decider against England the day after Paddy's Day, while defeat effectively renders the rest of the season meaningless. It's a similar story for Wales, although the Triple Crown and Grand Slam are already out of their reach following their opening day loss to England. Still, the retention of the championship they won with such style last year is surely enough of an incentive.

This afternoon they're not the same proposition that they could have been. Firstly, there are the injuries, the multitude of ailments that have afflicted Wales over the past couple of months, from Ryan Jones's shoulder to Shane Williams's dead leg and right back around to Gareth Thomas's blood vessel problem. Which neatly leads us to the second reason why Wales aren't the same side as last year, the mysterious resignation of Mike Ruddock and all the shenanigans that have gone on in public view since.

They're a side clearly on the edge, but on the edge of what is the bigger question. Will the drama of the last 10 days galvanise them into something extraordinary, or will it contribute towards a mishmash of an effort that mirrors what's happening off the pitch?

It'll be interesting to watch Wales, sure, but even more so Ireland. They had their own farce on the pitch in Paris and how they respond to it, both tactically and mentally, will be absorbing and should tell us a lot as to where this side is actually heading under O'Sullivan. They appear to have grappled furiously in their own minds about the true worth of their performance against France and it still hasn't been sorted out.

The official line remains that they bossed the game but as the coach admitted during the week: "If we play Wales and make that many errors we won't win the game". That line, at least, rings true.

The word and sentiment coming from the Irish camp is that they'll mix their game tactically against Wales. It makes sense. The visitors are perceived to have something of a soft underbelly up front . . .

aside from their scrummaging powers . . . and besides that, we know by now that they like their games loose and fast and for Ireland to mirror that style of play would be something akin to rugby suicide.

"We've got to control the football and field position, " says O'Sullivan, "because they like an open game. But that doesn't mean we can't pass the ball. It's about balancing up the performance." In deference to all this, Scott Johnson has promised that his band of men will show their darker side. "Everyone has talked about the beauty in our game, but they haven't seen what has underpinned the beauty.

It's important that people understand that to be beautiful in rugby terms there has to be a bit of grunt as well."

The weather will have its effect on all of these plans, however, especially at Lansdowne Road. The forecast is for moderate to strong winds this afternoon and all plans concocted in the bunker during the week will have to be adapted to deal with the infamous wind tunnel at the ground. What a nuisance.

On the personnel front the loss of Paul O'Connell, the Irish talisman in their opening two games, is immense and probably something the team or the coach won't realise until they're out there in the heat of battle. Donncha O'Callaghan certainly won't let anybody down, while the return of Marcus Horan has to be welcomed. With regard to the other change from Paris, it's something of a puzzle that Andrew Trimble takes the place on the wing, not because Tommy Bowe deserved to start, but rather because an inexperienced centre has been selected to man the left touchline ahead of genuine wingers. Wales will no doubt be keen to test out the Ulsterman's true understanding of the position.

The outcome? We'll be looking for Ireland to produce a full 80-minute performance for the first time since they played England on a Sunday last March. In between we've witnessed seven below-average efforts on the trot (if you exclude the Japan tour), sprouting a whole host of question marks surrounding the set up. They're well capable of beating Wales but only a genuine performance, kickstarted with a bright and point-earning opening to the game, will tip things in their favour. A big day for the team and the coach. It will tell an awful lot.