Gibson, 20, was not even in the initial squad when it was announced, but impressed the Italian so much in the 'B' team fixture against Nottingham Forest last Thursday he was handed a late call-up.
Trapattoni said: "In international football, teams score goals from high balls.
"The first reason is his [Gibson's] height, the second is he plays with confidence.
"He is confident on the ball. He plays the easy ball and he looks before the ball comes. For me, that is a good quality.