The Irish team to play Argentina on Saturday looks suspiciously like a first-choice XV, but then again it's not quite full-strength. Malcolm O'Kelly's omission can probably be interpreted as a gentle kick in the derriere, while Matt Mostyn gets a start and will be looked at closely, as will replacement Mike Mullins before the management finalises Ireland's 30-man World Cup squad on Sunday.

Far less experimental than the selection for the game against Connacht last weekend, this side shows just three changes from the team beaten 32-26 by Australia in Perth last June. Conor O'Shea, injured in the first Test, returns at the expense of Girvan Dempsey at full back, Mostyn - an original selection for the Perth Test before withdrawing with a hamstring strain - returns for Jonathan Bell, while Davidson comes in for O'Kelly.

Describing the selection, manager Donal Lenihan revealed: "Within the 22 it mightn't be (a first-choice selection) if we were sitting down to play in the World Cup final tomorrow. There are still two or three places up for grabs in the World Cup squad and that's probably been reflected in the 22 that have been named."

This comment probably applies to the choice of Mike Mullins as a substitute back ahead of the more versatile Jonathan Bell, who can cover wing and full back as well, whereas Mullins is much more of an inside centre specialist. Similarly, there is no room for Dempsey, a regular on the left wing up until the first Test in Brisbane, and then very impressive at full back in the second Test.

Lenihan declined to go so far as to say that O'Kelly had been dropped. "In fairness, we have three locks there. Paddy Johns played in the second Test against Australia, as did Malcolm O'Kelly. I think both Paddy and Jeremy Davidson have shown a huge appetite to get on this team. We would have been slightly disappointed with Malcolm's performance last Saturday. Whichever two of those three is selected - and Bob Casey will obviously come into consideration as time goes on - it is an extremely competitive area in the team, and it's a healthy position to be in."

All the more so when you think back on O'Kelly's phenomenal return to the starting line-up in Perth after a six-month absence with a shoulder injury. Even allowing for his fateful knock-on, it was surely one of the outstanding, multi-purpose individual performances by an Irish player in the 1990s. That's Big Mal of course, and being Big Mal, he'd probably have resumed in the same manner had Leinster and Ireland been playing the Springboks, the Wallabies and the All Blacks over the last three weekends. But, perhaps lacking in motivation, he was outshone by Bob Casey in the Leinster game against Ulster, and then by Johns and Davidson last week in Connacht. Their form, fitness and hunger have been a real boon, all of which in turn should bring out the best in O'Kelly.

Aside from Mullins, the replacement selections have probably given the strongest pointers yet to a few of the vexed issues facing the management when they prune their preliminary 34-man into the final 30 for the World Cup.

Certainly the presence of Brian O'Meara and Eric Elwood as halfback understudies suggests they will start the World Cup in those roles, and that Conor McGuinness and Ronan O'Gara will miss out.

Of the two remaining conundrums, one concerns the wings, where James Topping and Matt Mostyn have perhaps moved ahead of the unlucky Denis Hickie. The real toss-up will then be the decision to either omit one of the five props - Justin Fitzpatrick, Angus McKeen or Reggie Corrigan - or else go with the entire quintet and omit one of the five centres, with Mike Mullins possibly now inching ahead of the unlucky Rob Henderson. He, like all his Leinster colleagues on Tuesday night, was given little or no chance to boost his claims.

Although the Pumas' depressingly easy bloodless win over Leinster was of limited value to the Irish management, as Warren Gatland observed, it was "helpful" in giving "a bit of a wake-up as to how tough the Argentinian side is going to be on Saturday."

The Pumas certainly impressed the Irish coach. "They played the game at pace, their handling was good, they were very strong up front, they defended well and overall were very strong in all areas."

A hard work-out on Saturday, it was suggested? "It will be more than a hard work-out," Gatland said. "They comfortably beat Scotland last week. They were up 31-8 until Scotland scored two last minute tries and they're trying to go through this tour unbeaten and it was good for a number of our players to be there (at Donnybrook) and see how strong they were, because they'll be under no illusions about how difficult Saturday's Test match is going to be."

Only two of the Argentinian side that played on Tuesday will line out on Saturday. Surprisingly, scrumhalf Nicolas Fernandez Miranda comes in for the live-wire Augustin Pichot, while Santiago Phelan replaces Rolando Martin at number six, as he did during the second-half on Tuesday.

Hooker Augustin Canalda plays his third game in eight days, while there are ostensibly two props on the bench, as loosehead Roberto Grau can switch to hooker. Grau is a frontrow team-mate of Paul Wallace's at Saracens, and the tight-head Mauricio Reggiardo is a tight five colleague of Davidson's at Castres.

The two changes are part of coach Hector Mendez's pre-tour decided revolving policy, though the likelihood is that Pichot and Martin will start the World Cup as first choices.

The referee for Saturday's Test, which is again sponsored by the Irish Permanent, will be Derek Bevan of Wales. There is also a change in the numbering of substitutes, as decreed by the International Board. Where before they began at 16 with the substitute backs and ended with the substitute front-rowers, now they are in reverse, though more chronological, order - beginning with the reserve hooker at 16 and culminating in the reserve three-quarter at 22.