The Republic boss will make wholesale changes for Tuesday night's friendly clash with South Africa at Thomond Park three days after seeing his senior men clinch a vital qualifier victory in Cyprus.
Manchester United defender John O'Shea has returned to his club for scans on a calf injury, while midfielder Aiden McGeady has been excused duty because of a knock.
With skipper Robbie Keane, Shay Given, Richard Dunne, Kevin Kilbane and Stephen Hunt also being released, the depth of the Italian's squad will be tested in full.
Only Sean St Ledger, providing he has not suffered any reaction to his knee injury, Keith Andrews and captain for the night Kevin Doyle of the XI who started in Nicosia will do so again in Limerick.
But Trapattoni has impressed upon those men who come in - Keiren Westwood, Stephen Kelly, Paul McShane, Eddie Nolan, Liam Lawrence, Darron Gibson, Andy Keogh and Caleb Folan will all play - that they need to prove to him they have what it takes to do a job in the remaining qualifiers and beyond if called upon.
He said: "When you go to a World Cup, you are going to have important players missing for big games."
Kick-off is at 7.30pm.