The Iranian international made 24 appearances for the club last season before an ankle injury sustained against Queens Park Rangers prevented him from competing in the final two months of the campaign.
However, Dejagah has played just once for the Whites this term, in the Capital One Cup win at Burton in August, and appears to be down the pecking order at Craven Cottage.
Bryan Ruiz and Damien Duff are ahead in Jol's plans while 20-year-old Buomesca Tue Na Bangna was preferred for Saturday's 2-0 derby defeat at the hands of Chelsea.
Jol has demanded high standards from the former Wolfsburg attacker.
"I want a number one in every position," he told the Fulham Chronicle. "On that wing I've got Dejagah, Damien Duff, Bryan Ruiz and Mesca. They have to fight for their place.
"The only thing I say to Dejagah is you have to show us that you're the number one, and the same applies to Damien."
The 27-year-old joined Fulham on a three-year deal in 2012 from Bundesliga side Wolfsburg for a reported fee of 2.5million euros.