Felipe Anderson won the first Rome derby of the season for Lazio on Sunday with the only goal in a scrappy 1-0 victory over Roma which moved his team third in Serie A.
Brazilian Anderson struck the winner just before the half hour mark in the Italian capital after Roma defender Roger Ibanez gave the ball away cheaply in his own area.
It was the 29-year-old's third league goal of the campaign as he continues to play in the unfamiliar position of centre-forward in place of injured Ciro Immobile.
Italy striker Immobile was on the bench supporting Lazio despite a thigh problem leaving him unable to play and he watched his team go into the top four with an assured performance.
Lazio are level on 27 points with fourth-placed Atalanta, eight behind league leaders Napoli, and will stay third regardless of how Inter Milan do against arch rivals Juventus in Sunday's late match.
Inter sit three points behind Lazio in sixth place and will take fourth spot from Atalanta if they win at the Allianz Stadium in Turin.
Known for his expansive brand of football, Lazio coach Maurizio Sarri has developed a team who are hard to beat and shorn of key man Sergej Milinkovic-Savic they soaked up Roma's largely ineffectual attacking and claimed a seventh clean sheet from their last eight matches.
The nominal home side at the Stadio Olimpico, Roma went closest to scoring four minutes after going behind when Nicolo Zaniolo's deflected shot smacked out of the crossbar.
But Jose Mourinho's side didn't create enough to deserve a win and drop down a place to fifth following their fourth defeat of the season.
Verona crisis continues
Earlier, Verona slumped to the bottom of Serie A on Sunday after losing 2-0 at promoted Monza, their eighth loss in a row.
Second-half strikes from Carlos Augusto and Andrea Colpani handed Monza their first win in four matches and left 10-man Verona on five points from 13 matches.
Verona, who lost Giangiacomo Magnani to a red card midway through the first half, have shown no signs of improvement since sacking Gabriele Cioffi and promoting novice Salvatore Bocchetti from the youth team last month.
Verona have won just once, in stark contrast to last campaign which was one of the club's best in years, and after the loss sporting director Francesco Marroccu apologised to supporters for the latest humiliation.
They are a point behind Sampdoria, who lost 2-0 at home to Fiorentina, and Cremonese who drew 2-2 at Salernitana on Saturday.
Monza stay 15th but are seven points clear of the relegation zone in their first ever Serie A season and were cheered on in the stands by stabbing victim Pablo Mari.
On-loan Arsenal defender Mari was one of several people attacked last weel in a Carrefour on the outskirts of Milan by a man who killed an employee from the supermarket after grabbing a knife from a shelf.
Fragile Torino forward Pietro Pellegri suffered yet another injury blow when he fell over and injured his ankle at kick-off of his team's 2-1 loss at 12th-placed Bologna.
Pellegri, who has one cap for Italy, slipped over just three seconds into the loss at the Stadio Dall'Ara and limped off the field in the fourth minute following treatment.
