Lyon coach Bruno Genesio is unable to offer assurances over Nabil Fekir's future at the club.
The France international forward was close to joining Liverpool in July before the Ligue 1 club withdrew from negotiations.
Chelsea, who defeated Lyon on penalties in an International Champions Cup meeting on Tuesday, have been linked with a move for the 25-year-old.
And Genesio is unsure if he will be able to call on the services of Fekir throughout the season ahead.
"It's too early to say," he told a news conference when questioned about the player's future.
"He wanted to leave at the end of last season, but came back to training yesterday and was happy. Who knows?
"There may be opportunities that come up before the end of the window. For now, he is a Lyon player."