Waterford FC have been forced to suspend all activity.
A second player at the club needs to undergo a test for COVID-19 after reporting symptoms this morning.
It follows the postponement of Tuesday night's SSE Airtricity Premier Division meeting with Sligo Rovers.
Waterford returned to action on Saturday with a 1-0 win away to Shelbourne in John Sheridan's first competitive game in charge.
However, this weekend's visit of Cork City to the RSC has been plunged into doubt.
The Sligo game was postponed after a player who travelled with the squad to Tolka Park, but didn't play, was sent for testing having reported "flu-like symptoms".
The FAI say the second player was not involved in Saturday's win away to Shels.
It's reported that Waterford's club doctor - Sinead Fitzpatrick - resigned from her role on Tuesday morning, but it's not known if her departure is connected with either case.
FAI statement:
The FAI can confirm that a second Waterford FC player is to undergo a test after reporting suspected COVID-19 symptoms to the club this morning.
The player was not involved with the first team for their game against Shelbourne in the SSE Airtricity League Premier Division on Saturday.
The club has suspended all activity until the result of this test - and a COVID-19 test on a second player - are known.
The FAI and Waterford FC will make no further comment until test results are returned.
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