Roma's director of sport Walter Sabatini has urged fans to turn up in greater numbers, saying: "We are playing the best football in Italy."
The Stadio Olimpico was far from full for the crucial 3-2 Champions League win over Bayer Leverkusen on Wednesday.
And with a Rome derby against Lazio looming, Sabatini has called on the missing supporters to return to the fold.
"We are playing the best football in Italy," he told La Gazzetta dello Sport.
"Roma are loved, but this love is silent. It's not only the Curva [are of the ground], it seems like the whole stadium couldn't care less. I'm not worried -- I'm terrified."
His call comes after Roma president James Pallotta recently criticised the behaviour of some fans and said he could do without them supporting the club.
Security measures introduced by Rome's city council, which divide the Curva Sud into two, have led to boycotts, with supporters who usually congregate in that area accusing the club of not doing enough to back their cause.
But coach Rudi Garcia said the team needed them, adding: "The Olimpico has got to become hell [for opponents] -- we need our people.
"In Germany, when we were 4-2 up [against Leverkusen, a game that ended 4-4], the whole stadium lifted Bayer to get their equaliser. We could do with a bit more of that kind of warmth here."
Roma's late Champions League win on Tuesday took them above their Bundesliga opponents and into second place in the group.
Their next fixture is at Barcelona, before they conclude the group stage at home to BATE Borisov.