Recent signing Mladen Petric scored two goals in a game where Fulham did not miss Dempsey, however Jol afterwards left the door open for the American to return.
"We were talking about [Dempsey] and it means the other players have to step up their productivity," Jol told Sky Sports News.
"The other players didn't score enough last season but they have to now Clint is not there.
"Maybe [at] some stage in the future he will be involved again."
Dempsey scored 16 league goals for Fulham last season.