Each way is laced with potential pitfalls. For example, if O'Sullivan sends his front liners on duty in Argentina and just one player picks up an injury that rules them out of World Cup contention, say Brian O'Driscoll for example, then the coach will be pillared for chasing results on a pointless tour. If, on the other hand, he selects a shadow squad, he runs the very real risk of allowing his first-choice to go off the boil.

Take a peak at your rugby calendar. Ireland play France at the Stade de France on 21 September in their third World Cup pool game. Scroll backwards and you'll find that the last seriously competitive game his main men will have played in . . . and we mean seriously competitive, not the half-paced Magners League, the tame pre-World Cup friendlies or Ireland's facile World Cup pool openers against Namibia and Georgia . . . was on the Heineken Cup quarter-final weekend of 30/31 March. That represents a period of just under six months. Even the most blood-thirsty carnivore out there would struggle to remember what to do after half a year out of action.

It's a dilemma but there is a compromise. If O'Sullivan left, for example, the four players he absolutely cannot afford to be without . . . in our book, John Hayes, Paul O'Connell, Brian O'Driscoll and Ronan O'Gara . . . back at home, he'd not only ensure that the rest of his front-liners had an opportunity to rediscover their competitive instincts, he'd also be given an opportunity to discover viable alternatives to the foursome lest any of them should fall before, during or even after the World Cup.

That course of action makes perfect sense to us but all indications ahead of tomorrow's announcements, particularly after the utterings of O'Gara and Girvan Dempsey in interviews recently, are that O'Sullivan will opt to leave his entire first-choice XV, the ones who played most of the Six Nations, at home while bringing pretty much anybody who's in contention for a World Cup spot. That includes up to six players who are set to play some part in the Heineken Cup final, a game that takes place a day after the initial squad depart for Buenos Aires. The stragglers will depart to join up with their countrymen the day after the final.

Which brings up the question, how many World Cup slots are actually left? During the week Irish assistant coach, Niall O'Donovan, indicated in a newspaper interview that just 15, perhaps 20 places in Ireland's 30-man World Cup squad are set in stone but we think is slightly exaggerated. Realistically 25 places in the party are already filled, barring injury of course, leaving a good 20 players, many of whom will be on the tour to Argentina at the end of May, fighting for just five places.

We'll take it as given that O'Sullivan, and O'Donovan of course, will plump for 17 forwards and 13 backs in their squad, just as they did for the 2003 World Cup in Australia.

In the front-row, Jerry Flannery, Rory Best and Frankie Sheahan will travel as the three hookers, with Marcus Horan, John Hayes and Simon Best also certain to fill three of the four propping seats. The final spot will go to either Bryan Young, in the driving seat at the moment, or Peter Bracken, a likely Argentinean tourist.

In the second-row Paul O'Connell, Donncha O'Callaghan and Malcolm O'Kelly, if fit, are certainties to travel to France. That leaves room for one more second-row, with Trevor Hogan, Leo Cullen and Mick O'Driscoll all hoping to make an indelible mark on the management in South America.

Four of the six places in the back-row are also effectively filled, with Denis Leamy, Simon Easterby, Neil Best and David Wallace all sure to make France.

That leaves five players fighting it out for the other two spots. Shane Jennings, Alan Quinlan, Keith Gleeson, Jamie Heaslip and Stephen Ferris are the likely candidates here, with the two chosen ones likely to be decided on the back of their efforts in Argentina. It will be a ferocious competition.

In the backline, things are a lot more settled with just one place effectively up for grabs, unless the management decided on a 16/14 forwards/backs mix for the tournament. Peter Stringer, Eoin Reddan and Isaac Boss will all make the World Cup, with the summer tour likely to decide which one of the latter two is the Munster scrum-half 's understudy in the tournament. Ronan O'Gara and Paddy Wallace will be the out-halves, with Brian O'Driscoll, Gordon D'Arcy and Andrew Trimble making up the contingent of centres. Shane Horgan, a winger on our list, can of course fill in at centre if absolutely necessary, leaving Denis Hickie, Girvan Dempsey and Geordan Murphy (if his rift with the coach isn't significantly deep) as the other certainties.

That leaves room for just one more back and there's a host of bright young things, most of whom are likely to travel to Argentina, queuing up to grab it. Any one of Barry Murphy, Brian Carney, Kieran Lewis, Rob Kearney, Luke Fitzgerald, Tommy Bowe, Gavin Duffy or Daniel Riordan could fill that spot and again, the decision will most likely be made after O'Sullivan gets a good look at each one of them up close and personal this summer.

The truth is that all of them are good enough to travel.

In this context, it's interesting to look back on Ireland's summer tour before the 2003 World Cup. The trip to Australia, Tonga and Samoa saw Ireland's big players head home after the game in Perth, allowing a number to stake their World Cup claims on the islands.

Simon Easterby, for one, made such an impression on that tour that he worked his way to being a World Cup regular, while the decision by Ronan O'Gara at the time to travel to Tonga and Samoa, when he was given the opportunity to have a rest by Eddie O'Sullivan, certainly aided the Munster outhalf in his battle with David Humphreys.

Perhaps there are another couple of ambitious players out there who are at this moment persuading O'Sullivan to take them to Argentina. As for the rest of the likely tourists who're going to have to dog it out against the Pumas, those five World Cup spots represent their slim incentive.

HIGH FIVE: WORLD CUP PLACES UP FOR GRABS

PROP The candidates Bryan Young (Ulster), Peter Bracken (Wasps) Favourite Young would appear to be ahead in O'Sullivan's thinking at this moment in time, but he doesn't appear fully convinced about the Ulsterman just yet. You could say the same thing about his views on Bracken but a good summer tour could still swing it for the Offaly man.

SECOND ROW The candidates Trevor Hogan (Leinster), Leo Cullen (Leicester), Mick O'Driscoll (Munster) Favourite If we go by Six Nations thinking, Mick O'Driscoll is the coach's favoured option but both Cullen and Hogan have had impressive club seasons. Again, whoever does the business in Argentina will book their place on the plane to France.

BACK ROW (x2) The candidates Shane Jennings (Leicester), Alan Quinlan (Munster), Keith Gleeson and Jamie Heaslip (both Leinster), Stephen Ferris (Ulster) Favourites Not all that cut and dry. Heaslip has a slight advantage as O'Sullivan is likely to want to take a second specialist number eight, but it mightn't be as simple as that. Quinlan has long been admired by the Irish coach, while Ferris is also highly regarded. Then again, Jennings and Gleeson are the only natural sevens in the mix and that could be an serious advantage.

Argentina will tell a lot.

UTILITY BACK The candidates Brian Carney (right), Barry Murphy (both Munster), Rob Kearney, Kieran Lewis, Luke Fitzgerald (all Leinster), Tommy Bowe (Ulster), Gavin Duffy, Daniel Riordan (both Connacht) Favourites Like the back-row issue, it could easily be any one of the above. Barry Murphy is probably slightly ahead of the rest because he's been a regular for his province over the past two seasons but O'Sullivan could opt for the precocious youth of Fitzgerald or Kearney.

Another extremely interesting battle in Argentina.

Ciaran Cronin