Lee O'Connor set up the third goal in a 3-1 win over New Zealand as the right-back won his first Republic of Ireland debut before making his Celtic debut.
The 19-year-old has yet to play for the Scottish champions since signing from Manchester United this summer.
But he was part of Mick McCarthy's experimental side in Dublin as players were rested ahead of Monday's must-win Euro 2020 qualifier with Denmark.
O'Connor played 90 minutes and provided a telling cross for Callum Robinson.
The Sheffield United forward's headed goal completed the Republic's comeback after New Zealand debutant Callum McCowatt gave the All Whites the lead after half an hour.
Blackburn Rovers defender Derrick Williams equalised on the stroke of half-time before Preston North End forward Sean Maguire edged them in front and the head of substitute Robinson ensured a comfortable victory.
All were scoring their first goals for their country.