He said: "Ryan has been in a little bit of a tug-of-war between the Republic of Ireland and Scotland and the Irish were hoping that with his family connections, they'd get him.
"Thankfully from Scotland's point of view, he has opted to play for us and I am sure he will go with the Under-20s to Canada for the World Cup this month. I'll be very surprised if he doesn't.
"He has all the credentials to make a name for himself in the game. He'll certainly go on to play at a high level and I believe he will play for the full Scotland team in the years ahead.
"Seeing Naisy make his Scotland debut will be a great boost for Ryan and all our boys because it shows it can be done. Ally McCoist and Ian Durrant played for Scotland while at Kilmarnock but they had already won caps when they were with Rangers.
"It was nice to see Naisy coming on for his debut as it showed we can bring players through and they can go all the way to playing for Scotland.
"I'm delighted for him to do it at such a young age as well. He can still play for the Under-21s but it shows how much he has come on and how much people think of him that he has a full cap.
"Naisy has come through and done it and shown that playing at Kilmarnock is no barrier to playing for Scotland and it was ironic he should replace Boydy, who also came through our ranks.
"The big plus for me was that Steven didn't have to put a Rangers strip on to get that first international cap!"