Felipe Caicedo snatched a late winner to keep Lazio third in Serie A with a 2-1 victory over Sassuolo on Sunday, just ahead of city rivals Roma, who beat Brescia with England defender Chris Smalling involved in all of his side's three goals.
Champions Juventus maintained their grip on the top of Serie A with a 3-1 win at Atalanta on Saturday, to stay one point ahead of Inter Milan who eased past Torino 3-0.
The two Roman outfits are now third and fourth respectively before Cagliari, a point behind in fifth, play lowly Lecce later on Sunday.
"It's an important success," said Lazio coach Simone Inzaghi.
"Third place consolidated? It's still early, we are there and the others too, every day things can change."
Serie A top-scorer Ciro Immobile struck to put Lazio ahead on 34 minutes with his 15th league goal this season.
But struggling Sassuolo pulled a goal back through Francesco Caputo just before the break.
Ecuadorian Caicedo came off the bench to seal a fifth consecutive league win in injury time to keep Lazio seven points behind Inter Milan in third place.
Roma are now two points behind their local rivals after defender Smalling scored and set up the other two goals in a 3-0 victory over bottom club Brescia.
Smalling, on loan from Manchester United, headed in the first from a corner in the 48th minute at the Stadio Olimpico.
The 30-year-old then provided the cross that allowed fellow defender Gianluca Mancini to volley in eight minutes later, with Edin Dzeko completing the rout on 66 minutes after Smalling's headed assist.
"Sometimes you have to raise your voice," said Roma coach Paulo Fonseca of his halftime pep talk.
"We didn't play with great intensity and aggressiveness in the first half, we were slow, that changed after the break."
Smalling added: "Long may this continue because we've got some big ambitions this season and we need to keep improving each game.
"I'm enjoying my football and I think the team, as you can see, is enjoying our football too. We need to keep going because there is a long way to go yet."
Brescia, now coached by 2006 World Cup winner Fabio Grosso, remain rooted to the bottom of the table.
Forward Mario Balotelli was dropped for Sunday's game because of his lack of commitment in training.
The Italy international tried to play down Thursday's training ground bust-up with Grosso.
"Recovery! Coming back soon, for the moment let them talk," the former Marseille attacker said in a post on Instagram showing him undergoing physiotherapy.
But Grosso insisted he was not ready to take back the 29-year-old as the promoted side fight for top-flight survival.
"Mario can be a protagonist in this team if he has the will, the determination and the enthusiasm, which he has so often lacked," said Grosso.
"When you are at the bottom of the table like us you need more than a player who knows how to hit the ball hard and score when he can.
"We need someone ready to work for the team, fight hard for the 90 minutes."
Elsewhere, Samuel Di Carmine scored the only goal as Verona piled the pressure on Fiorentina, despite Franck Ribery returning after his three-match suspension.
The Tuscany side are in 10th place with just one point from their last three games.