Rarely will the score be so immaterial this season, but rarely will some of the sub-plots count for so much. Today's World Cup warm-up game between Connacht and Ireland at the Sportsground (4.00) and Tuesday's match between Leinster and Argentina are not quite on the level of a Final Trial, but they're not a million miles away either.

The bottom line is that come next Sunday or Monday week at least four of the 34-man preliminary World Cup squad will miss the cut for the October odyssey. It's quite calculatingly ruthless when you think about it, and the areas of contention seem straightforward enough.

Presuming Eric Elwood fends off Ronan O'Gara as the second out-half, and that either Brian O'Meara or Conor McGuinness emerge as the second scrum-half, then the other choices facing the Three Wise Men would appear to be on the wing and, most probably, in midfield and maybe prop.

This obviously makes this afternoon's scrum-half head-to-head between McGuinness and O'Meara the nearest thing to a final showdown. That's the way O'Meara sees it and McGuinness assuredly knows that he is at least equally in need of an impressive showing.

No matter how the balance of the squad pans out, it's hard to see how the four wingers currently in the squad would be accommodated along with Girvan Dempsey. Justin Bishop is well ensconced, having started a dozen successive Tests on the rightwing and though not the best of them going forward, he is the best defensively and has a high workrate.

This leaves three into two, namely Matt Mostyn, James Topping and Denis Hickie. Mostyn and Topping play for Ireland today, and Hickie leads Leinster on Tuesday. Mostyn, with five tries in four games for Ireland, possibly leads the queue, so Topping has a huge amount to play for today.

As this afternoon's chosen midfield of Kevin Maggs and Brian O'Driscoll is also Ireland's first-choice pairing, more interest may centre on Mike Mullins when he comes on and then on Rob Henderson on Tuesday. Shane Horgan's unexpected return to action could make this the most competitive area of the lot.

Conceivably, three of this quartet (Henderson, Mullins, Johnny Bell and Horgan) could be named in the World Cup squad. Alternatively just two of them would allow the management to go with an extra forward in a 17-13 breakdown and accommodate a fifth prop. Another, less obvious or likely option (given the ruling which permits a replacement during the tournament at 48 hours' notice) is a third hooker.

If the selectors opt for four props, then they would have to pick two from Justin Fitzpatrick, whose improved fitness levels were given special mention by Donal Lenihan during the week, Reggie Corrigan and Angus McKeen. The investment in John Hayes's undoubted abilities around the pitch has not been returned in his scrummaging and McKeen has thus emerged as a dark horse. Good showings by McKeen in fitness testing and training this week, and in today's game, may convince the management that they have a tighthead who can lock the scrum and enable them to rest both Peter Clohessy and Paul Wallace should the need arise in, say, either the second pool game against Australia or the third pool game against Romania.

For all the while, they will be planning their strategy with a view to playing as many of the 30 squad members as possible in some shape or form.

Another possible area of debate will be the back row where David Wallace will be guesting for Connacht today and will be keen to keep the pressure on Kieron Dawson, who will also be closely observed on Tuesday as Leinster's guesting openside.

The sheer infectious enthusiasm of Alan Quinlan, another Munster guest, will assuredly have buoyed up Connacht this week. Unlucky with injuries this past year, his World Cup dream looks to have passed him by barring something out of the ordinary, but that is unlikely to stop him from taking on Ireland with ball in hand at every opportunity.

Elsewhere in the putative World Cup squad, the quartet of locks looks an open and shut case, as does the full back issue. But here again, today's offerings will help shape the pecking order within the squad. For example, the dream pairing of Jeremy Davidson (who needs to show his best form before the World Cup) and Malcolm O'Kelly gets its first-ever start for Ireland. And as Girvan Dempsey had a fine second Test in Perth and is now playing well at full back for Leinster, Conor O'Shea is under more pressure than he's been for some time.

Collectively, for Connacht it's a chance to regroup and exorcise some of the ghosts of the last two Saturdays at the Sportsground. For Ireland, it's an ideal opportunity to re-establish some of the basics before seeking to up their game another few notches against Argentina this day week.

"The score is irrelevant," maintains Warren Gatland. "For ourselves, we've got to identify and make sure our set pieces are strong, that our organisation is there, that we're accurate with the calls in our lineouts and scrums, defence, our kick-offs, and our back row stuff, and then see if we can get a bit of continuity."

Though the potential for embarrassment is obvious, Ireland should today achieve their goals and much more.

Connacht: S Allnutt; P Duignan, M Deane,M Murphy, N Carolan; E Elwood (capt), C McGuinness; J Maher, S McDonald, M Cahill, J Duffy or C Rigney, A Quinlan, B Gavin, D Wallace. Replacements: McIvor, B Glynn, G Brady, K Flanagan, J McVeigh, E Brennan, C Rigney or B Jackman.

Ireland: C O'Shea; J Topping, B O'Driscoll, K Maggs, M Mostyn; D Humphreys, B O'Meara; J Fitzpatrick, R Nesdale, A McKeen, J Davidson, M O'Kelly, T Brennan, D O'Cuinneagain, A Ward. Replacements: to be announced.