Racing 92's entire squad and backroom staff have been placed into immediate home isolation after nine positive tests for coronavirus plunged preparations for their Champions Cup final against Exeter into turmoil.
The club are implementing a series of emergency measures to halt the further spread of Covid-19 ahead of their clash with the Chiefs in Bristol on October 17.
On top of sending all players, management and support staff into quarantine, the Parisians' training centre is being closed for a minimum of five days to undergo "complete decontamination of the site".
New tests will be carried out next week with the results dictating when individual and team training can resume, according to a statement released by Racing, who have not disclosed the identities of the nine.
The Top 14 league match against La Rochelle on Saturday has been postponed, but the hope is that they will be able to undertake their fixture against Toulouse a week later before facing Exeter at Ashton Gate.
Although there is no suggestion the Champions Cup final is under threat, were more positive tests to be returned next week then tournament organisers EPCR would consider activating their two-step resolution process a week early.
First a match assessment panel made up of a medical advisory group would judge whether the game is safe to go ahead. If the answer to that is no, then a match resolution panel would convene.
It is the same process that led to the cancellation of Leicester's Challenge Cup quarter-final against Castres last month after three players and one member of staff from the French visitors tested positive. That decision was made 24 hours before kick-off.
Three positive tests amongst the playing squad triggers an automatic postponement in the Top 14, but that rule is not in place for European action.
Even if Racing report a clean bill of health next week, disruption is a major setback as the big-spending French heavyweights attempt to win their first Champions Cup title after finishing runners-up twice.
"EPCR has noted the announcement of several positive Covid-19 tests at Racing 92 and sends its best wishes to the club and to each person affected," a statement issued by tournament organisers read.
"EPCR will be following its full, robust protocols regarding the Heineken Champions Cup final on October 17 and will remain in contact with Racing 92, Exeter Chiefs and the French league throughout."
Exeter boss Rob Baxter insists the news is a reminder of the disruption that can be caused by Covid-19.
"It's something we'll have to look at, but the reality is that it's something we don't want to think about too much," Baxter said.
"It could be nine players well outside their first team squad, or four of them could be members of staff and the others are training normally as a group.
"We are continually telling the players that it's what they do away from the club that's the most important thing.
"When you turn up to the club – and I know I have to be a little bit careful here – it's virtually impossible to catch Covid in the facility because everyone here is being tested regularly.
"If someone tests positive they're isolated immediately. Everyone is health checked and temperature checked every day.
"The reality is that Covid only comes in if someone brings it in, so it's what you do away from the facility that's important and we're constantly reminding the players of that.
"Because as we've seen, any little mishap can lead to a big problem."