Gera has joined a long list of players in the treatment room after suffering a knock to his knee in training.
Out of action: Gera (right) is unable to play against portsmouth
Andy Johnson is still struggling with his knee injury while Paul Konchesky (foot), Simon Davies (ankle), Clint Dempsey and John Pantsil (both knee ligaments) are all out.
Loan signings Nicky Shorey and Roma striker Stefano Okaka are both poised for their Fulham debuts.
Provisional squad: Schwarzer, Hangeland, Shorey, Baird, Hughes, Stoor, Kelly, Duff, Murphy, Nevland, Zuberbuhler, Greening, Riise, Dikgacoi, Smalling, Elm, Zamora, Okaka.
Fulham snap up Liverpool youngster Christopher BuchtmannKamara leaves Fulham for Celtic as Hoops also pick up Motherwell's SlaneNew Fulham loan signing Okaka eyes long-term stay at Craven Cottage Shorey joins Fulham on loan with view to permanent switch from Aston Villa FULHAM FC