The SPFL pair are in contention to feature in Scotland's upcoming fixtures against Peru and Mexico.
Both players have been in great form for their respective clubs, and former performance strategy head McClair is happy to see young players being called up.
"It does no harm for them to be coming into the international set-up and be involved and playing against top players because it gives you a different view, particularly the ones that are not involved in European games, to say that other countries of a similar size or even greater populations do not necessarily have national teams with players that are better than ours," McClair told reporters.
"Part of it is they have to be playing. If any team is buying a player, they have to have a plan of exactly what they are going to do with them. And again that's down to opportunity. If you're talking about Kieran Tierney, there was an opportunity - Celtic needed a left-back. He came in, did very well, continued to do very well and has made that position his own. You have to have a belief in what you are doing with young players, and more and more I think that is going to be prevalent in the next couple of seasons.
"The opportunity presents when clubs need you to play. A lot of that comes down to economic circumstances. The more young Scottish players are promoted into first-team squads, it will be of huge benefit to Scottish football."
McClair had memorable tenures at both Celtic and Motherwell prior to joining Manchester United in 1987.