Roma have second place firmly in their sights after closing to within four points of Napoli with a humbling 4-1 derby victory over Lazio at the Stadio Olimpico.
Napoli's loss at Udinese earlier on Sunday effectively ruled them out of the Serie A title race and they now face a battle to keep hold of the runners-up spot after Roma's impressive display in the capital.
Stephan El Shaarawy got the ball rolling with a first-half opener and Edin Dzeko put clear daylight between the two Derby della Capitale foes with a second goal midway through the second half.
Marco Parolo threatened an unlikely Lazio comeback when halving Roma's lead but Alessandro Florenzi notched his first derby goal to settle the tie, with Diego Perotti adding late gloss to the result.
Any faint hopes Lazio had of reaching the Europa League are surely now extinguished, while Luciano Spalletti's Roma can start bidding for automatic entry into the Champions League group stage.
Despite the fervour emanating from the stands, the derby started at a calmative rhythm with both defences coping well with early raids and sighters.
In the 15th minute El Shaarawy ensured the match would be a contest by opening in the scoring. Lucas Digne's floated cross met the on-loan AC Milan striker's head and Roma had drawn first blood against their fiercest rivals.
Lazio seemed listless and unable to respond for the rest of the half and Roma almost doubled up when Miralem Pjanic hit a post when Biancoceleste goalkeeper Federico Marchetti looked beaten.
Then, on the stroke of half-time, Roma's Belgian pass master Radja Nainggolan let rip after forcing his way into a shooting position, but the ball fizzed just wide.
When play resumed Roma continued asserting their dominance over their struggling opponents as Mohamed Salah came within inches of plundering the second goal.
That honour fell instead to Dzeko who, in the 64th minute, tapped the ball over the line after Perotti had clattered a post.
Lazio almost forced their way back into the clash when Wesley Hoedt nodded against the crossbar, with Wojciech Szczesny soon touching Parolo's header away from danger.
The former Parma midfielder would slash the deficit in the 75th minute. Szczesny rushed out to anticipate Miroslav Klose's attempt to convert Keita's cross and Parolo was there to clean up.
Roma needed to react quickly lest they waste the chance to close the gap on Napoli and captain Florenzi provided the answer with seven minutes remaining.
From the scramble that followed a Pjanic corner, the Italy winger connected with the ball to volley home at the far post, sparking wild celebrations.
Lazio were cowed and meekly submitted to a fourth goal in the final minutes.
After robbing the ball from a crestfallen Parolo, Perotti bore down on Marchetti before rifling home left-footed from the edge of the area.