Trapattoni is looking at the 19-year-old's continued progress for club and country.
He said on www.elevenaside.com
"In Italy, when there are young players like McCarthy, for example, who have much potential, all the reporters and fans have great expectations when they talk about them.
"But the player must play continuously. They grow and develop their personality. I think he is clever and plays good football. He is also creative.
"But only Pele and maybe Maradona and Cruyff were great at 19 years old. The rest grow slowly, slowly."