Roma failed to put full pressure on Serie A leaders Inter after Alessandro Diamanti's late free kick snatched a 1-1 draw for strugglers Livorno on Saturday.
Champions Inter can extend their lead over second-placed Roma to six points if they win at Torino in Sunday's late game.
Roma struggled to create many clear-cut chances and lost injury-prone captain Francesco Totti to a knee injury on the half-hour. They eventually broke the deadlock after 54 minutes when Montenegro forward Mirko Vucinic netted with a looping header after David Pizarro's clever chip into the area.
Livorno barely threatened but shocked the hosts seven minutes from time when Diamanti curled the ball into the near corner of the net. The Tuscan side remain in the relegation zone but are just a point behind fourth bottom Parma, who host Napoli on Sunday, and have four games remaining.
Fiorentina, looking to strengthen their hold on fourth spot and a Champions League qualifying place, host inconsistent Palermo later on Saturday.