Roma took the lead when Lamela hit a left-footed shot low into the bottom corner beyond Zebrette keeper Zeljko Brkic.
In a fairly tentative first half, Daniele De Rossi had a chance to double the vistors' lead, but he hit a shot high and wide of the goal from the edge of the box after 41 minutes.
After the restart another chance for Aurelio Andreazzoli's side went begging when Marquinho headed over the bar from close range on 57 minutes.
Five minutes later, the home side had their equaliser when Muriel dispatched past
Maarten Stekelenburg after a through-ball from Maicosuel.