Fulham manager Martin Jol believes that striker Dimitar Berbatov's form is important for his side to achieve their objectives this season.
The 31-year-old has scored five goals in 14 Premier League appearances for the Cottagers, who are currently 13th in the table.
"If things are going well then everyone will be happy with him but if things are not going well then he can be unhappy," Jol told reporters.
"He is used to winning games at the clubs where he was, so we have to talk to him. He has to put in the same attitude and workrate that he always did before.
"When he does that there is no problem but he is certainly a player who we have to keep on his toes. We hope he does well for us because we were very happy with him for the first few months."
Fulham will host Southampton on Boxing Day.