The former Ajax shot-stopper picked up a new shoulder injury during the week and will most likely not be at 100 per cent in time for the match against the Partenopei
The Dutch custodian was ready to return to the squad after missing the club's 2-1 defeat against Fiorentina in midweek, but a shoulder injury forced him to miss Friday's training session.
It is believed that Stekelenburg will not recover in time for Saturday's contest, which will open room for Gianluca Curci to be between the sticks against the Partenopei.
Roma coach Luis Enrique has more selection problems for the match, as Erik Lamela, Pablo Osvaldo and Daniele De Rossi are all ruled out because of suspension.
The Giallorossi lie in seventh position in the Serie A table, four points behind Napoli, who sit fourth.