Looking to move on from a disappointing Euro 2012 finals, which saw Ireland lose all three group games, the 73-year old Italian has injected fresh blood into the squad ahead of the 2014 World Cup qualifiers.
With Shay Given announcing his retirement from international football on Monday, Trapattoni and new captain John O'Shea hinted that other players, namely Robbie Keane, Damien Duff and Richard Dunne, could follow in the goalkeeper's footsteps.
"Shay told me he would make himself available in case of an emergency, but it is yet to be seen what the other senior players will decide," Trapattoni told a news conference on Tuesday.
"Of course, I would like to have all of them at my disposal for the opening World Cup qualifiers against Kazakhstan and Germany, but the very purpose of the friendly against Serbia is also to see how well the youngsters can replace them."
O'Shea added: "They've been fantastic players for Ireland and if they decide to stay on, brilliant, if they decide to finish, they deserve that choice.
"We can't do much about it, it's up to the lads, it's their choice and that's something that has to happen at some point in every player's career.
"Shay made a decision yesterday and we just have to get on with it, now is the time for the new lads to step up and I have no doubts that his replacement Keiren Westwood will be able to fill the void."
Trapattoni's opposite number Sinisa Mihajlovic axed several Serbia regulars after a dreadful European Championship qualifying campaign, with captain Dejan Stankovic and defender Nemanja Vidic also retiring from international football.
Mihajlovic suffered three defeats in as many friendlies in June against Spain, France and Sweden, using an unfamiliar 3-4-2-1 formation.
With only one out-and-out striker in his squad, former international defender Mihajlovic will now try to apply a blueprint copy of Spain's Euro 2012 striker-less but potent formation in his last warm-up before the World Cup qualifiers.
"We will switch to a 4-3-3 system with as many attacking midfielders as we can deploy, because we need several options in order to avoid being predictable," he said.
"Of course, we would like to have more strikers available, but they have to earn their spot in the squad by playing and scoring more regularly for their clubs.
"The Ireland game is a perfect dress rehearsal for our opening two qualifiers away to Scotland and at home to Wales because they all have a similar style of play and I will hence be looking for a result against the Irish."
Mihajlovic, who won the European Cup with Red Star Belgrade as a player in 1991, conceded that Serbia's bitter Balkan rivals Croatia were the favourites to win a delicately balanced group that also includes Belgium and Macedonia.
"They had a solid Euro 2012 and will therefore be confident, but Serbia and Belgium should also be in with a shout."