Two Senior Leinster Rugby players have tested positive for Covid-19.
The province confirmed the news on Tuesday morning.
They say "a number" of close contacts to these players are self-isolating.
One of these players tested positive after showing symptoms and feeling unwell.
The province then tested 104 players and staff for the virus on Monday with 103 tests returning negative results with one senior player testing positive.
Leinster Rugby is assisting two senior players who have tested positive for Covid-19.
— Leinster Rugby (@leinsterrugby) December 29, 2020
Leo Cullen's side are due to take on Connacht in the Guinness PRO14 in Dublin on Saturday but that game may now be in doubt.
Their St. Stephen's Day derby with Munster at Thomond Pak already had to be postponed last week due to an investigation into their Covid-19 PCR testing.
Results of the investigation would not have been returned in time to meet guidelines set by public health authorities.
The full Leinster statement on Tuesday morning read:
"Leinster Rugby is assisting two senior players who have tested positive for Covid-19.
"One player was tested outside the PCR testing window, after feeling unwell, and is now self-isolating.
"Further PCR testing was carried out at Leinster Rugby yesterday morning on 104 players and staff and 103 tests returned negative results with one senior player testing positive and he is also self-isolating.
"A number of close contacts of the two players have been identified and these players are also self-isolating.
"The HSE has been informed in accordance with public health guidelines.
"The Leinster Rugby squad return to training later on today."
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