Stade Francais have cancelled a friendly against Toulon as players who tested positive for coronavirus have developed lesions on their lungs.
L'Équipe last week reported that up to 25 positive tests have been returned at the Top 14 club.
Stade were due to face Toulon next Thursday, but the Paris giants on Wednesday revealed that match will not go ahead as some players who contracted COVID-19 must rest for at least another week.
"In light of the mandatory medical examinations for all players who have tested positive for the COVID-19 RT-PCR test, it appears that some of them are carriers of lung damage due to the virus," a club statement said.
"These lesions require a period of complete rest estimated for the moment at a minimum of one week and which will be added to the fourteen already observed.
"Other reviews are currently under way.
"In addition, the input of the medical commission of the National Rugby League for an advisory opinion resulted, for obvious health reasons, in the cancellation of the friendly match against RC Toulon scheduled for August 27.
"Once again, the club would like to thank all those who have shown their support during these last days."
Stade are due to get the new season started against Bordeaux-Begles on September 4.