Steve Staunton has advised his senior players at home to sit up and take note of the performances his young rookies are putting on in the United States.

The Republic of Ireland round off their US tour against Bolivia on Saturday night at the Gillette Stadium near Boston, with Staunton set to field another inexperienced side, just as he did against Ecuador in New York on Wednesday night.

Staunton gave debuts to seven players with four more coming on as substitutes in the 1-1 draw with Ecuador at Giants Stadium.

Now more of the same could happen when the Irish take on a Bolivia side Staunton believes will pose a tougher test than that offered by their South American rivals in midweek.

With the competition for places intensifying ahead of September's Euro 2008 qualifiers in Slovakia and the Czech Republic, Staunton suggested another good display in America will spur on the more established players who were unavailable or injured for the tour.

He said: "Everybody's going to take notice, especially if, please God, we get another good result.

"If it's a good performance tomorrow night I'm going to be delighted and people will take notice, of course they will.

"But you've got to remember, senior players are senior players and when it comes to big important games the most important people you need are your senior players.

Staunton remained tight-lipped on the team he will send out, save for revealing that Barnsley's Nicky Colgan will win his ninth cap starting in goal by replacing Birmingham City's Colin Doyle between the posts.

The Irish boss said he would make one or two other changes and said that the after-effects of an energy-draining Giants Stadium pitch on Wednesday night would also dictate selection in part, as will searing daytime temperatures at kick-off on Saturday.

"I think we've adapted well, we've had to," he said. "The enthusiasm will be there but the pitch was sapping and didn't do us any favours.

"We're going to freshen it up and we're going to have enthusiasm again but you've got to remember it's going to be 100 degrees at 4pm tomorrow so there's a bit of everything going into it.

"Yes, we want to win the game but we want to see what players can do."

Staunton cancelled training on Friday, preferring to send his players to the gym and swimming pool in order to prepare for the expected extreme heat.

He reported a clean bill of health for his squad, including captain Kevin Kilbane, who took a knock against Ecuador but has recovered.

On the Bolivians, Staunton said: "This will be a tougher test against a more experienced side than Ecuador, at least if it's the same side that went to South Africa and won 1-0.

"They know each other's jobs, which is a sign of a team that's been together for a while and I think that's great from our point of view.

"I think our younger lads are going to learn an awful lot. They play a little bit different to Ecuador, more 4-3-3, or 4-3-1-2, with two strikers that split wide with an old-fashioned number 10, a flair player."

The Bolivian set-up will not influence Staunton's own formation, however.

"I think I've got a nice little system going, he said. "It's 4-4-2 but its flexible and within that 4-4-2 we adapt," he added.