IRELAND coach Les Kiss has thrown down the gauntlet to his young squad ahead of Saturday's Test against the US Eagles in Houston.
The Australian will provide the continuity from old regime to new when he hands over the reins to Joe Schmidt after the tour.
The new coach will be in Texas to run the rule over the squad when he touches down on Friday and watches the clash at the BBVA Stadium on Saturday.
With 10 players away with the Lions and a number of others injured or rested, Kiss has a host of new faces to pick from. There are seven uncapped players in his squad.
And with Schmidt taking over ahead of games against New Zealand, Australia and Samoa there will be little chance for manoeuvre in November, meaning players need to take their opportunities in Texas and Toronto.
"Every test is a must-win game," said Kiss. "There is a real opportunity on two fronts, to bring players away so that they are well informed about what is required at this level and to prepare for Test matches come November.
"For ongoing transition into a new structure there is an opportunity to know what the players can do.
"These two Tests are ideal for that. It is a long time since we last played these boys in 2011, it was 60 minutes before we got away from it was tough, right until the back end.
"It is a different team, the US have variation on their gameplan, their attack is better and they are improving.
"We want to win two tests, That's what it is about and if we come out the other end well informed about what faces us going into November it will be a good thing."
The decision on whether to introduce water breaks has not yet been made with the game expected to be played in high temperatures and humidity. The call will be made at the match committee.
Ireland captain Peter O'Mahony admitted the going had been tough at training.
He said: "The heat has been a factor for us and in training today we got 70 minutes and a bit of a shock of what heat and humidity will do, training has gone well and it is an opportunity to get good Test rugby."
With 18,000 tickets sold at the 22,000 capacity Texan venue, there is a feeling that the USA could shock the under strength Irish team, but coach Mike Tolkin is expecting a massive step up even from their last Test against a tier one nation when they played Italy last year at the same venue.
"Certainly, when you play Italy and Ireland they are two different styles," he said.
"Ireland's games are tremendously skilful. In some displays there was real explosiveness, it is apples and oranges really.
"Ian Madigan is a player who makes things happen, he is a spark plug and we have looked a lot at him."
The USA have had their squad bolstered by the return of their European-based players and Barbarians Taku Ngwenya and Samu Manoa who played against the Lions last week.
Ireland have no injury worries ahead of the Test.