Uncapped Smith sustained a side strain and was withdrawn from the squad for the historic match.
Nathan Smith, Ireland's 22-year-old fast bowler, has been ruled out of the team's historic first Test against Pakistan with a side strain.
Craig Young, the fast bowler, has been called in as Smith's replacement.
Smith, who is uncapped in all formats, could not practise in the training session on Wednesday 9 May and has been withdrawn from the squad.
Young, 28, has played 13 one-day internationals and 15 Twenty20 Internationals for Ireland and made his international debut in 2014. He has 27 ODI wickets and 10 T20I wickets in addition to 43 wickets from 10 first-class matches at 23.23.
Barry McCarthy, one of those unlucky to miss out on selection initially, picked up an injury in his latest county match for Durham, thus ruling him out of contention to replace Smith, Cricket Ireland said.
Ireland, who were granted Test status last year, will play their first Test against Pakistan in Dublin from Friday 11 May.
They are also scheduled to play two T20Is against India on 27 June and 29 June.
Ireland squad for the one-off Test against Pakistan: William Porterfield (c), Andrew Balbirnie, Ed Joyce, Tyrone Kane, Andrew McBrine, Tim Murtagh, Kevin O'Brien, Niall O'Brien (wk), Boyd Rankin, James Shannon, Craig Young, Paul Stirling, Stuart Thompson, Gary Wilson (wk)