Glasgow have been forced to call off next week's derby clash with Edinburgh after reporting four players have tested positive for coronavirus.
Warriors have already seen this weekend’s Heineken Champions Cup clash with Lyon axed after 20 members of their squad were forced to self-isolate.
That decision came after the players were ruled to have been close contacts of last week’s opponents Exeter, who have had their own Covid outbreak at Sandy Park.
Now their Guinness Pro14 showdown with Richard Cockerill’s capital outfit a week on Sunday has also been postponed after four of the quarantined players returned positive test results.
The Scotstoun side said in a statement: "Glasgow Warriors’ home 1872 Cup fixture against Edinburgh in the Guinness Pro14 on Sunday 27 December has been postponed.
"The club has four confirmed positive cases of Covid-19, amongst the group of 20 players that are already in self-isolation, and the results of another round of testing this morning are pending.
"This follows the cancellation of the Heineken Champions Cup fixture against Lyon, which was also due to be played at Scotstoun Stadium.
"Glasgow Warriors have consulted, and sought the support of, Scottish Rugby’s Threat Management Group over the postponement of the game.
"In addition, having considered all the available evidence, the Pro14 Rugby Medical Advisory Group has deemed that this fixture cannot go ahead as scheduled.
"Pro14 Rugby will examine potential dates in early 2021 to reschedule the game. At this stage, there is no impact on the second 1872 Cup fixture, scheduled for Saturday 2 January, at BT Murrayfield."
The organisers of the Pro14 added: "We will examine potential dates in early 2021 to reschedule the game."