Marseille coach Andre Villas-Boas on Wednesday urged support for the club's players infected by coronavirus after three new cases took the number of infected at the Ligue 1 club to four.
Tuesday's positive tests saw the French league forced into postponing the opening match of the 2020/21 season, which had been scheduled to be between Marseille and Saint-Etienne on Friday.
"Unfortunately we live this week between a certain anxiety and bad news," Villas-Boas said.
"The pandemic that stubbornly continues to scare and affect so many families has ended up knocking on our door."
Villas-Boas vowed that "we will soon be together again".
"It's the moment to be careful and to support others and at the same time keep hope for the time ahead."
Some 40 players from 11 clubs have tested positive for COVID-19 in recent weeks.
The vast majority contracted the virus after resuming training in June, leading to quarantine and a flurry of cancelled pre-season matches.
The latest to be named as positive for the virus on Wednesday was Montpellier striker Andy Delort -- the seventh player at the club to have contracted the disease since the start of the pandemic.
"I will come back very soon, I am fine," said Delort, who was Montpellier's top scorer in the league last season with nine goals.
Montpellier coach Michel Der Zakarian was forced into cancelling Wednesday morning's training session after the positive test, while the club's friendly against Metz on Saturday was called off.
The entire Montpellier squad is to undergo further testing Thursday.
Meanwhile Nimes' opening match with Brest on Sunday could also be postponed after they registered four new cases this week.
"All positive players are in isolation at home. While three of the four players are currently asymptomatic, the fourth has lost taste and smell," said the club in a statement.
In the hope of avoiding the match being pushed back, the entire Nimes squad will be tested again on Thursday morning, with results scheduled to be announced later that day.