Celtic will be without manager Neil Lennon and 13 first-team players for Monday's Scottish Premiership match against Hibernian after they were deemed close contacts of defender Christopher Jullien, who has tested positive for coronavirus.
The Scottish champions were already facing criticism for a controversial mid-season training camp in Dubai, while Scotland is under a national lockdown to halt rising infection rates of Covid-19.
The trip has backfired on the Glasgow giants. Jullien is currently sidelined with a knee injury and is expected to be out for up to four months and had only travelled to the Emirates to continue his rehabilitation.
While the rest of the Celtic squad have tested negative, they were in close contact with Jullien during flight and team coach travel.
"While all of the other members of the squad and backroom team have tested negative, we have been informed by the authorities that, having been deemed 'close contacts', Celtic manager Neil Lennon, assistant John Kennedy and 13 first-team players will be required to self-isolate on a precautionary basis as required by the current regulations," Celtic said.
Scotland's First Minister, Nicola Sturgeon, questioned the reasons behind the trip last week with only essential travel allowed under the current restrictions.
Elite sports teams are allowed to travel for matches and training.
Celtic said they had applied rigorous protocols for their trip, which they insisted had been for "performance reasons".
Dubai is a popular destination for European clubs for warm-weather training at the start of each year, with Celtic regular visitors over the past few seasons.
"The reality is that a case could well have occurred had the team remained in Scotland, as other cases have done in Scottish football and across UK sport in the past week," the statement said.
Celtic are chasing a historic 10th consecutive league title, but have fallen 22 points behind runaway leaders Rangers, albeit with four games in hand.
All professional Scottish football below the top two tiers was suspended on Monday due to the soaring infection rates.
The Premiership and second-tier Championship will be exempt from the new three-week shutdown provided strict testing protocols are followed.
Britain is struggling to contain a new, more transmissible strain of Covid-19, which has cranked up pressure on the national health service.
The Scottish Football Association board said the suspension of the lower leagues had been agreed after a meeting between the Scottish FA and the sports minister.
It will take effect from midnight on Monday.
Scottish FA president Rod Petrie said: "While the national sport has been afforded the privilege of elite sporting exemption, the risk of mass transportation of untested, largely part-time players is something that cannot be sustained as the cases continue to rise and available hospital beds become increasingly scarce."
The suspension will last until January 31 and will be regularly reviewed. The Scottish Cup will also be suspended.
