The veteran winger’s current contract expires at the end of the season, meaning he is able to discuss a free transfer with other clubs next summer during the winter months.
Craven Cottage boss Martin Jol is keen to keep hold of the 33-year-old, who has netted three goals so far this season.
The Dutchman told The Chronicle that he has little concern regarding the Irishman’s fitness and that he wants him to stay:
“We’ve still got time. Damien’s not the youngest player in the world so we will do that in the next couple of months.” He said.
“He was a very important player and was always in the top three with his fitness, although he’s a bit older.
“He’s one of the best pros you will ever see and always give 100 per cent. If he’s fit you would always like to keep him.”
Duff joined the West Londoners in 2009 and has gone on to make nearly 100 appearances in the white shirt.
He enjoyed, arguably, the finest spell of his career with Blackburn Rovers before moving to Chelsea during the early days of Roman Abramovich’s spending.
With first-team opportunities limited he joined Newcastle in 2006 before eventually swapping the North East for Fulham.