Fulham expect Brian McBride to be out until Christmas after the injured striker underwent surgery on a dislocated knee-cap.
The Cottagers captain damaged his knee when scoring in last weekend's 2-1 defeat by Middlesbrough and has returned home to the USA to start his rehabilitation.
"He is having an operation and we expect him to be out until Christmas," revealed manager Lawrie Sanchez.
"He is captain, he is a centre-forward who wins a lot in the air and is a big presence in the dressing room.
"So he is quite a big loss for us."
Meanwhile, Sanchez has confirmed he is interested in bolstering his strikeforce and also signing out-of-favour Celtic midfielder Thomas Gravesen.
The former Real Madrid and Everton schemer has fallen out of favour at the Scottish champions.
"We are looking for new players," added Sanchez.
"I still think the squad is thin despite what has been said about how much has been spent.
"We lost seven first-teamers from last year and another couple of signings would certainly help the equation."