Nicola Murru was inches away from equalising with a rasping shot from the edge of the box that struck the post, before Lazio substitute Ciro Immobile smashed a free kick off the crossbar and Sampdoria striker Gregoire Defrel shot wide at the end of a breakaway with the goal at his mercy.
Lazio stay eighth with 55 points but just three points separate them from fourth-placed AS Roma. Torino, Atalanta and AC Milan all have 56 points.
“There are 12 points left to play for, there is time and space for anything to happen,” Lazio coach Simone Inzaghi said.
“We know what our situation in the table is and we don’t want to give up a single centimetre... we will give everything we’ve got.”
Ninth-placed Sampdoria have 48 points with four rounds remaining.
(Reporting by Alasdair Mackenzie, editing by Pritha Sarkar)
