The Italian coach conceded that the Canaries midfielder had always impressed him but stressed that his Ireland team needed to play with two strikers against Austria and Sweden
The Italian tactician explained that, while he was impressed by the former Shelbourne man, he preferred to play with two strikers and noted that Hoolahan plays in a different system at club level.
"We know [Wes] Hoolahan very well," Trapattoni told the Irish Times. "But we need two strikers and at his club he plays with just one."
He continued: "We have seen him many times for his club and he always plays well but it is in this position. Club football is not international football, psychologically, it is different and we cannot let the opponents think that we are afraid.
"We do not know how Sweden will play against us but they will be confident and there might be space. Shane Long is fast, he can play well and give us strong options out wide."
The former Juventus coach also praised Aston Villa defender Ciaran Clark, who opened the scoring for the Boys in Green at the Aviva Stadium.
"Clark is good," said Trapattoni. "Last year he was not playing so much at Aston Villa but he's strong, confident, can head the ball and he is a good passer of the ball."
He added: "It's not easy when there is pressure but I talked with the centre backs and I told them there are times when you don't need to take the ball. You can wait because the striker must do something and tonight Clark showed that he is getting more experienced."
Meanwhile, Trapattoni believes that Derby County midfielder Jeff Hendrick 'can get better' after impressing on his debut.
"He [Hendrick] is good and I think that he can get better. He is physically strong, plays with good balance, he has a good pass, comfortable thinking before he receives the ball, I think he will improve with us," said the 73-year-old.