Leinster's PRO14 trip to Llanelli is off, after the Scarlets reported a number of positive Covid-19 cases in their squad.
The game, which was meant to take place on Sunday afternoon, will now be rescheduled for a date in 2021.
The Scarlets were beaten by Ulster in Belfast on Sunday - with the Irish province waiting on their own test results to come through today.
A PRO14 statement reads:
"The game was due to take place on Sunday, November 29 in Llanelli, however, a small number of Scarlets players have returned positive cases of Covid-19 and others identified as close contacts are now isolating. Having considered all of the available evidence, the PRO14 Rugby Medical Advisory Group has deemed that this fixture cannot go ahead as scheduled.
"Ulster Rugby, who played against Scarlets on Sunday, carried out routine squad testing today and will receive their results in the next 24 hours.
"PRO14 Rugby will examine potential dates in early 2021 to reschedule the game.
Leo Cullen's side next outing will be their Heineken Champions Cup opener against Montpellier in just over two weeks.
The province's latest round of PCR tests came back negative, while they've sent their wishes across the Irish seas.
"Leinster Rugby PCR testing took place in UCD yesterday, Wednesday, and returned no positive results from the 104 tests taken.
"Everyone at Leinster Rugby wishes the Scarlets players affected a speedy recovery and we hope to see them back in action very soon."
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