The West Londoners are currently one place above the drop zone with seven points from their seven Premier League games, which has seen the Dutchman come under pressure at Craven Cottage.
"That would be a bit of a disgrace to Fulham," Sky Sports News quotes him as saying.
"For them they have had a mixed bag of results recently and then people were talking with a new owner and speculation grows, but Martin is a very shrewd cookie and they have got all sorts of players there.
"Scott Parker is fit again and when you look at it they are used to this division. I'm sure they will have much bigger aspirations than ourselves and the truth is we have got to try and finish first of the bottom four."
Palace have won one and lost seven on their return to the Premier League.