West Brom forward Callum Robinson has been confirmed as the Republic of Ireland player whose positive test for Covid-19 was announced on Tuesday.
Robinson will miss the Republic's friendly against England at Wembley on Thursday and the Nations League games against Wales and Bulgaria.
Brighton's Aaron Connolly is also out of the three games because of injury.
A Football Association of Ireland statement said Connolly had been injured in training on Tuesday.
Preston forward Sean Maguire has been called up as a replacement while Swansea City's Ryan Manning will also link up with Stephen Kenny's squad before Sunday's game against Wales.
It's another piece of bad luck for Connolly, 20, after he had to miss last month's Euro 2020 play-off semi-final defeat in Slovakia following a Covid-19 false positive involving a member of the FAI staff which also forced Norwich's Adam Idah out of that match.
Connolly had been selected to start in Bratislava with fellow striker Idah due to be on the bench.
It later emerged that the pair, who had moved seats on the plane, could have been involved after all following news of the false positive.
Five more players - including Robinson - were ruled out of the Republic squad on the morning of the subsequent Nations League game against Wales after being deemed close contacts of another unnamed team member who had tested positive for Covid-19.
Last month's Republic triple-header was then capped off by another player missing the Nations League 1-0 defeat in Finland following a positive test for coronavirus as manager Kenny remained without a victory in his opening five games in charge.
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