Adam Idah was inexplicably an unused substitute during Republic of Ireland’s 2-0 defeat to Greece last night. The Celtic striker has started the season well since making his mega-money move to Glasgow on a permanent basis with four goals in 10 appearances. One of those strikes came at the top level in the Champions League as he sprang from the sidelines to net in a 5-1 mauling of Slovan Bratislava but the 23-year-old has admittedly still had to settle for minutes off the bench. READ MORE: Celtic man Liam Scales speaks out from international camp after scoring crucial Ireland goalStill, Idah’s …