Republic of Ireland manager Stephen Kenny lost five players just before Sunday's Nations League clash against Wales after a positive coronavirus test in the squad.
The Football Association of Ireland announced that an unnamed player had tested positive just three days after Republic forwards Aaron Connolly and Adam Idah missed the Euro 2020 play-off defeat against Slovakia because of what is now believed to be a false positive test.
As a result of Sunday's positive test, four Ireland players deemed to be close contacts were stood down.
"Stephen Kenny's Ireland squad has received one positive Covod-19 test result ahead of today's Nations League game against Wales at the Aviva Stadium, after the latest round of UEFA testing," an FAI statement said.
"A player - who cannot be named at this time - tested positive on Friday after a negative test on Monday but his case is not related in any way to that of the backroom team member who tested positive on Monday last.
"Talks with the HSE late last night identified four other players as close contacts of this positive case and they have been stood down from the matchday squad for today's game against Wales."
Kenny was able to name only seven substitutes, including two goalkeepers, for the Wales game, with Blackburn defender Derrick Williams also missing from the 18-man squad.
Speaking before the game, Kenny told Sky Sports: "We got some results nearly into midnight last night, so five of the players are not available today.
"To be honest with you, we haven't had any coronavirus in the camp at all - the previous case was a false positive, so all of the other arrangements that we've made were in vain, really, because it was a false positive, so this is the first case we've had. We haven't had it at all.
"Unfortunately, we've had a case and four close contacts on the flight. Four who would have been starting today, actually, in the team that we were picking are out today, so that's the way it is. We just have to contend with that."