Ireland Tour of Argentina:If nothing else, Ireland look refreshingly different this week. The core of the team has remained cast in stone for years save for jaunts with various Pacific Islanders or the Japanese, but a new mix of the relatively tested and untested went through a rigorous session on a bone-hard pitch in temperatures exceeding 20 degrees in the Centro Naval sports club in the eastern suburbs of a teeming Buenos Aires yesterday.

Mosquitos have been the main enemy thus far, obliging the squad to spray themselves with repellent at the outset of yesterday's session. The Pumas' bite is liable to be worse. Although Argentina themselves are without their French-based frontliners, nevertheless roughly two-thirds of their likely starting line-up will be professionals based overseas, and no less than the home-based players, will be fired up by playing at home in Santa Fe's first Test match as well as fighting for World Cup places themselves.

In similar circumstances, as O'Sullivan reminded us, they beat Wales last year by 27-25 in Puerto Madryn and 45-27 in Buenos Aires.

Yet despite the absence of Ireland's 15 frontliners, there may still only be one new cap in the starting line-up for Saturday's first Test in Sante Fe, which Eddie O'Sullivan will name today.

The Ireland coach has not disguised his admiration for the uncapped Brian Carney, who seems certain to start the first Test and possibly even both in order to further his rugby union education, and is also a fan of Gavin Duffy, whose return to Connacht was in part instigated by O'Sullivan.

Tommy Bowe, one of the few Ulster players to have maintained his form, may complete the outside three. O'Sullivan has intimated that the Munster-bound Kieran Lewis will be tried at inside centre, with Andrew Trimble and Barry Murphy having a run each at outside centre.

Paddy Wallace, confined to just the last three minutes against England in the Six Nations, is the only viable option to start both Tests unless Jeremy Staunton is called out from Churchill Cup duty at short notice next week.

Isaac Boss is set to start at scrumhalf with Tomás O'Leary joining the inexperienced prop Tony Buckley on the bench.

Insiders also suggest the pack will comprise Bryan Young, Jerry Flannery and Simon Best in the frontrow, with Trevor Hogan partnering Malcolm O'Kelly at lock and Neil Best, Keith Gleeson and Jamie Heaslip being giving first crack in the ultra competitive backrow.

Frankie Sheahan is one of only four members of this 30-man squad who took part in Ireland's last tour here in 2000, with O'Kelly the only player to have played in the 34-23 defeat in Buenos Aires, and Sheahan recalls it as "the most intimidating venue I can remember, even though I didn't actually take the field.

"We were warming up around the dead ball area and they were shouting and roaring, and throwing things. There's something about the terraces, the north and south ends; they're rushing forward and back, and really getting involved in it. On the day I think we didn't really perform, some of the players had played in the Heineken European Cup final the week before."

Sheahan played in the autumn Tests whereas Gleeson hasn't played for Ireland since last summer's tour of New Zealand and Australia, and, incredibly, last started a Test match against Italy in Lansdowne Road in March 2004.

Quinlan, one of the non-playing members of last summer's tour, has only started one Test, in Japan two summers ago, along with three stints from the bench, since rupturing his shoulder in scoring that priceless try against Argentina in the World Cup four years ago.

"I've bittersweet memories of that day. To play in a World Cup was a fantastic environment to play in, and I'd love to achieve that again. It was great to score the try but the injury set me back a couple of years and my involvement since has been a bit stop-start."

So began a cursed four-year cycle, also featuring a long-term knee injury, and then a punitive suspension this season when he was in flying form, with only a hard-earned comeback for a replacements' stint in last season's Heineken European Cup final to lift the gloom.

"It's been a difficult period, and to be involved in the Heineken Cup final gave me a huge boost and gave me a bit of enthusiasm and energy for rugby again. I'm delighted to be back in an Irish squad and it's probably the last opportunity I'll have to make the World Cup," admitted Quinlan who, like the under-pressure O'Kelly, is seeking to partake in his third successive Coupe de Monde. You wouldn't want to be standing in his way.

Then there's the young tyros seeking to muscle their way into O'Sullivan's RWC '07 plans, such as the uncapped O'Leary and Robert Kearney, nicknamed Squirrel and Shooter on tour, the latter supposedly in reference to his own claims as a darts player.

"The fact that we're all fighting for World Cup places is another incentive," said Kearney of his first senior tour. "When you pick any team, it's always ruthless; there's only so many places going. That's part of life, and you win some, you lose some. This is a prime example of only getting one crack and you can't put too much pressure on yourself. You have to be relaxed and approach it as any other game."

Welcome to the last chance saloon.