Roma have second place firmly in their sights after closing to within four points of Napoli with a 4-1 derby humbling of Lazio at the Stadio Olimpico.
Napoli's loss at Udinese earlier on Sunday did major damage to their Serie A title bid and they now face a battle to keep hold of the runners-up spot after Roma's impressive display in the Eternal City.
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 contest, with Diego Perotti adding late gloss to the result.
Lazio's response to the heavy defeat was to sack head coach Stefano Pioli and replace him with their former striker Simone Inzaghi, the younger brother of recent AC Milan boss Filippo.
Gonzalo Higuain will miss key games in the run-in after being sent off as Napoli's Scudetto challenge suffered a severe blow in the shape of a 3-1 defeat at relegation-battling Udinese.
Higuain's 30th league goal of the campaign proved inconsequential as Bruno Fernandes' first-half brace was added to by Cyril Thereau before the Argentinian striker saw red 25 minutes from time.
He had to be restrained by several team-mates following his second yellow card as he put his hands on the referee and tried to confront Felipe, who was the recipient of the kick which earned the striker his marching orders, before he shoved a member of Napoli's staff as he went down the tunnel.
Milan risk missing out on European football once again after slumping to a 2-1 defeat to Atalanta.
Sassuolo could soon snatch sixth place from the ailing Rossoneri, who conceded an overhead kick to Mauricio Pinilla and a second-half goal from Alejandro Gomez at the Stadio Atleti Azzurri d'Italia.
Summer signing Luiz Adriano had given Milan an early lead, but his penalty was not enough.
Sampdoria boss Vincenzo Montella earned a point on his return to Fiorentina as his side hit back to claim a 1-1 draw.
Goals from Josip Ilicic and Ricky Alvarez ensured the spoils were shared in Tuscany, with the dropped points doing more harm to Champions League-chasing Fiorentina.
Samp, who survived losing Joaquin Correa to a late red card, can take comfort from edging away from the drop zone as the season enters its home stretch.
Struggling to escape the bottom three are Palermo and Frosinone, who were both beaten.
The 18th-placed Sicilians, who have not won since January, slumped to a 3-1 defeat at Chievo as goals from Fabrizio Cacciatore, Nicola Rigoni and Valter Birsa rendered Alberto Gilardino's first-half strike irrelevant.
Frosinone are a point behind Palermo and have the worst defence in the division, an unwanted accolade which was exacerbated by Suso's hat-trick in a 4-0 home win for Genoa.
The former Liverpool midfielder claimed the matchball after scoring three goals past beleaguered Frosinone, who also witnessed Luca Rigoni getting on the scoresheet at the Stadio Luigi Ferraris.
In the late game, Andrea Belotti's penalty completed a surprise comeback as Torino beat nine-man Inter Milan 2-1 at San Siro.
The Nerazzurri dominated the first half after taking the lead with a Mauro Icardi spot-kick, but Cristian Molinaro replied for the visitors after the break.
Both Miranda and Yuto Nagatomo saw red for Inter before Belotti completed the turnaround.
Source: PA
