The Sunderland winger has been warned he is lucky to still be a part of Ireland's squad for tomorrow night's friendly after his comments on Twitter at the weekend.
James McClean apologises for rant ahead of Ireland's friendly with Oman
The 23-year-old vented his fury at being an unused substitute during the Republic's 2-1 win over Kazakhstan on Friday night, describing his experience in Astana on Twitter as a "******* joke".
But the outburst came close to ending his international career after Trapattoni admitted he only decided to retain the midfielder for tomorrow's friendly against Oman out of necessity.
"Another manager, English or German, would have said take your bag and go home, but I might need him in the game to score a goal," Trapattoni admitted.
"He was mortified. If he could have, he would have eaten his words. He was very apologetic.
"I said to everyone this is not about respect for the manager, this is about respect for everyone. I said the players are your colleagues.
"If I don't play him, I can play others. There was Stephen Kelly and Kevin Doyle on the bench. They have many caps.
"The matter is closed now. With the young we need to have patience.
"Sometimes they say things they regret."
Trapattoni confirmed however the winger would once again start on the bench against Oman with the Italian planning to give 20-year-old Manchester United winger Robbie Brady a chance to impress at Craven Cottage, after last week becoming the Republic's record goal scorer at Under-21 level.
"He's a (type of) player we are missing," Trapattoni said.
"(He has) vision - he sees the pass immediately - he can shoot and works hard and he is also intelligent."