The increase of positive coronavirus cases among French clubs over the last few weeks has cast doubt over the start of the 2020-21 season, sources have told ESPN.
The new season is due to start in two weeks' time but 18 players have tested positive for the virus since clubs have returned to training, including four at Lille and three at Nantes.
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Marseille are due to host Saint-Etienne at the Stade Velodrome on Aug. 21 to kick off the season but positive cases among administration staff has thrown that fixture into doubt.
Sources have told ESPN that the league is working to calm fears about a possible surge in cases and are "monitoring closely" any developments.
This could include introducing a stricter testing and contact testing regime as well as increasing the quarantine period from seven days to 14.
"What we want to avoid is games being postponed once the season has started," a manager in Ligue 1 told ESPN, who spoke on the condition of anonymity.
"It is a very congested campaign already and we can't afford to move matches. So the league will have to take their responsibilities and us manager will have to accept to play with maybe two or three players missing because they are positive, like if they were injured."
A cluster of cases arose after a friendly between Montpellier and Strasbourg in July when nine Strasbourg players and one Montpellier player tested positive for the virus.
Montpellier, who have players from their reserve team in quarantine, released a statement on Thursday criticising Strasbourg's attitude for not testing their players again once their first case was announced.
The club have had to cancel two friendlies as a result of the positive tests and put one of their best players, Florent Mollet, into quarantine.