Callum Robinson, Alan Browne and Liam Scales will all join up with the Republic of Ireland squad ahead of Saturday's World Cup qualifier against Azerbaijan.
Robinson, who started the Championship season impressively with West Brom, had been ruled out of the Portugal game after testing positive for Covid-19, while Preston's Browne was identified as a close contact of a separate coronavirus case.
Both have completed their 10-day self-isolation period in the UK and have been called up to the squad.
Liam Scales receives his first call-up to the senior squad one week after completing his move from Shamrock Rovers to Celtic.
Dara O'Shea and Nathan Collins have been ruled out of the game against Azerbaijan and Serbia through injury.
West Brom defender O'Shea limped off during the first half of Wednesday night's defeat to Portugal following a challenge on Diogo Jota.
The Ireland squad travelled back to Dublin on Thursday and will train at the Aviva Stadium on Friday afternoon in preparation of the Azerbaijan match.
Republic of Ireland Squad:
Goalkeepers: Caoimhin Kelleher (Liverpool), Gavin Bazunu (Portsmouth, on loan from Manchester City), James Talbot (Bohemians)
Defenders: Seamus Coleman (Everton), Matt Doherty (Tottenham Hotspur), Shane Duffy (Brighton and Hove Albion), John Egan (Sheffield United), Ryan Manning (Swansea City), James McClean (Wigan Athletic), Andrew Omobamidele (Norwich City), Liam Scales (Celtic)
Midfielders: Josh Cullen (Anderlecht), Jeff Hendrick (Newcastle United), Conor Hourihane (Aston Villa), Harry Arter (Nottingham Forest), Jamie McGrath (St. Mirren), Jayson Molumby (Brighton and Hove Albion), Alan Browne (Preston North End)
Forwards: Aaron Connolly (Brighton and Hove Albion), James Collins (Cardiff City), Daryl Horgan (Wycombe Wanderers), Adam Idah (Norwich City), Troy Parrott (MK Dons, on loan from Tottenham Hotspur), Ronan Curtis (Portsmouth), Callum Robinson (West Bromwich Albion)
