Lazio closed in on second-place Inter Milan thanks to a late Miroslav Klose strike at the Stadio Olimpico which earned Vladimir Petkovic's side a 1-0 victory.
Inter hit the post twice in a game which came to life in the second half, but it was the Germany international who decided matters in the 82nd minute to reduce the gap between the two sides to a single point.
Inter's fifth defeat of the season leaves them four points behind league leaders Juventus, who can extend their lead at the top with victory over Atalanta on Sunday.
The game needed the first half to get going with neither side conjuring up a shot on goal inside the first 45 minutes.
The only flutter of excitement came three minutes before half-time when Klose pointed to where he wanted the ball to be delivered, but clipped the heal of Alvaro Pereira as he tried to get there, and his claims for a penalty were waved away by the referee.
The game then came to life in the second half with Inter hitting the woodwork twice in a strong five-minute spell.
Fredy Guarin was first to rattle the post with a shot from 25 yards in the 67th minute, with Antonio Cassano hitting the same part of the goal frame from slightly closer in the 72nd minute.
Each time, the rebound fell to Diego Milito, who first shot wide and then was denied by Federico Marchetti.
In between, Hernanes curled a free-kick over the wall but into the arms of Inter goalkeeper Samir Handanovic.
Klose then took centre stage, missing two easy chances before scoring the most difficult one.
He first failed to control the ball just five yards in front of Handanovic's goal with the ball trickling to the Inter custodian in the 79th minute.
Two minutes later, Klose's control again let him down as he burst into the area, but again failed to get a shot in.
It was third time lucky in the 82nd minute though, as the German made up for his previous stumbles with a shot on the stretch which he guided into the far post as he again fell to the ground.
Inter launched a late assault on the Lazio goal, but failed to find an equaliser as Lazio held on for the win.