The 61-year-old takes charge of his first game of Ireland on Friday evening and has challenged his players to prove they deserve a place in the national side.
"I don't want the players to treat these like friendly games. I told them that last night," Sky Sports News quotes him as saying. "These are very, very important. It's a bit like I would have treated pre-season, which was all about the players getting fit.
"If I was going into a club for the first time, the first time I was meeting the players was in pre-season, then pre-season became very important.
"They became big games because I have to make judgements on players. That's exactly how I see these games coming up. They may not be competitive in terms of picking up points, but they are very important."
Following Friday evening's friendly with Latvia, the Irish will face Poland in Poznan on November 19.