McCarthy knows he has a manager who has been supportive, particularly in the early stages of his Ireland career when there was so much uncertainty over his commitment to the cause.
He said: "The gaffer is different class. I was with him for four years and I know exactly the way he wants to play. Now I've got to et working hard on and off the pitch and it's not going to be easy.
"We didn't really get to have a chat about what he wants from me as it was that late to get the paperwork done and I had to come here.
"It was just a quick chat and he told me to go enjoy the two games and try and get maximum points for your country. Now it's down to business with Ireland and the move is done which I'm delighted about and I'm excited about the qualifiers."
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