Gonzalo Higuain scored twice to give Napoli their first win in four Serie A games as Milan were beaten 3-1 at Stadio San Paolo.
Adel Taarabt's debut goal had given Clarence Seedorf's Milan an early lead on Saturday, but Napoli were not to be denied a deserved victory.
Gokhan Inler equalised soon after, and Higuain struck twice after half-time to take his Serie A goal tally to 12 for the season and give Rafael Benitez's men their first league win since a 3-0 triumph at Verona on January 12.
Napoli, who were beaten by Atalanta in Serie A last weekend and Roma in semi-final of the Coppa Italia in midweek, dominated from start to finish and are now only three points behind second-placed Roma - who have two games in hand.
Defeat for Milan was their first in the league since Seedorf took over as coach last month, but the Dutchman may count his blessings that his side were not beaten by a more handsome margin.
Napoli defender Faouzi Ghoulam replaced the injured Anthony Reveillere and Dries Mertens came in for Jose Callejon, who started on the bench along with January signing Henrique.
Michael Essien and Taarabt made their Milan debuts, while striker Mario Balotelli returned from suspension as Seedorf made six changes to the side that drew with Torino last weekend.
Napoli made a bright start, but they were caught out after only seven minutes when QPR loanee Taarabt raced forward before placing a measured right-foot strike into the far corner of the net from just outside the area as the home defence backed off.
The goal was harsh on Benitez's team, but they were level three minutes later courtesy of a fine left-foot strike from Inler that took a deflection and looped over Christian Abbiati.
Milan struggled to cope with Napoli's attacking threat, and Higuain was inches away from putting the home side in front when his shot flashed wide of the far post.
Abbiati was lucky to escape with only a yellow card after 22 minutes when he rushed out of his area and upended Mertens after the winger had raced onto a through ball and attempted to lob the veteran goalkeeper.
To add insult to injury, Abbiati kept out the resulting free-kick from the Belgium international, before Marek Hamsik's venomous left-foot volley flashed just wide.
Christian Maggio then hit the post from a tight angle and Lorenzo Insigne headed just wide as Milan somehow went in level at the break.
Kaka replaced fellow Brazilian Robinho at half-time, but his introduction failed to turn the tide as Napoli maintained the upper hand and Abbiati could only watch on as Insigne's strike flashed wide.
It was only a matter of time before the home side took the lead, and it was former Real Madrid man Higuain who put them in front when he headed home an inviting cross from Inler 11 minutes into the second half.
The Argentina striker was a constant menace and he ought to have given Napoli breathing space but missed his kick after evading the vulnerable Philippe Mexes.
Napoli could have been made to pay for not making their dominance count but Taarabt's strike was kept out by Pepe Reina and then Balotelli failed to capitalise after the Spanish goalkeeper had totally missed his kick.
Higuain sealed the points with eight minutes left, though, slotting home from close range after Callejon picked him out.
|88||G. İnler||11' 38'|
|9||G. Higuaín||56' 82'|
|Coach: Rafael Benítez|
for L. Insigne 78'
for M. Hamšík 83'
for G. İnler 89'
|Trigger-happy Palermo president Zamparini resigns|
|Donnarumma is better than me - Zoff|
|Roar! United star Ibrahimovic says he´s a lion|
|Moore to replace Ayre as Liverpool CEO|
|Henderson doubtful for Liverpool´s crunch clash with Arsenal|
|Leicester had fire in their bellies - Shakespeare pleased to ink first win|
|Thank God we aren´t playing tomorrow - Klopp tears into woeful Liverpool|
|Vardy hits back at Leicester critics after sinking Liverpool|
|Leicester City 3 Liverpool 1: Vardy at the double in reminder of Ranieri´s glory|
|Srivaddhanaprabha: Leicester players not behind Ranieri sacking|
|Juventus without trio for Napoli semi-final|
|AFC Champions League Review: Lokomotiv score after 19 seconds, Lekhwiya grab draw|
|Kane could break Shearer´s record, says Spurs legend Mabbutt|
|Manchester City miss leader Hart - Wilson questions Guardiola call|
|Iniesta hoping for Luis Enrique stay at Barcelona|
|Atletico´s Hernandez given community service after domestic violence charge|
|Man of the moment Gabbiadini has ´no hard feelings´ towards Napoli|
|Spanish? I struggled with Italian! – Allegri reacts to Barcelona rumours|
|Gotze ruled out for unknown period with ´metabolic disorders´|
|Rabiot would have to consider Real Madrid offer|
|Isco and Morata deserve more minutes, concedes Zidane|
|Imagine if they didn´t let Messi and Neymar in! - Aurier episode sparks UEFA chief´s Brexit concerns|
|Ibrahimovic is ´running Manchester United dressing room´|
|New Everton Lukaku contract ´99.99999999 per cent done´|
|Ibrahimovic: Manchester United future does not depend on Champions League qualification|
|Allegri expecting ´angry´ Napoli|
|Ferguson disagreed with the world on Pogba´s value, says Raiola|
|Wolfsburg hire Arsenal academy boss Jonker as head coach|
|Raiola refuses to confirm Ibrahimovic will stay at Manchester United|
|Donnarumma deserves to play in a great team - Agent|
|Le Tissier: Man United would not have had Gabbiadini strike disallowed|
|Riviere - We do not regret Balotelli signing|
|Tianjin Quanjin tore up agreement to sign Falcao|
|PSV keeper Zoet bemoans Feyenoord´s ´f***** up´ Hawk-Eye winner|
|Ibra revels in trophy-winning exploits - but did he take a dig at Arsenal?|
|Evra: We disrespected Marseille after Le Classique humiliation|
|Marcelo: LaLiga in Real Madrid´s hands|
|Garitano sacked by LaLiga strugglers Deportivo|
|Klopp talks down player power|
|Dembele worth £50m and good enough for Real Madrid – Gamboa|
|´It´s very painful´ - Tadic heartbroken after final loss|
|´I was really upset´ – Fabregas struggled with lack of playing time|
|Cerezo: Torres renewal? We´re trying to bring Messi to Atletico|
|´He had the aura and confidence´ – Neville compares Ibrahimovic to Cantona|
|Neymar: Barca not thinking of Madrid or LaLiga rivals|
|Everything´s a plot against him - Ramos laughs off Pique theory|
|Wolfsburg part ways with Ismael|
|Lingard loving every minute of Wembley scoring streak|
|Pioli rues setback in Inter´s quest for Champions League|
|Zidane cools fresh Bale injury worries after stunning Real Madrid comeback|
|Pique fumes as Real Madrid benefit from controversial decision|
|Emery warns PSG against complacency|
|Gabbiadini scored three times, says frustrated Puel|
|Real Madrid equal longest scoring streak in Spanish history|
|Roma are fed up - Spalletti hits back amid penalty controversy|
|Lyon´s Memphis Depay revels in two-goal performance|
|Marseille 1 Paris Saint-Germain 5: Record crowd sees OM thrashed|
|Villarreal 2 Real Madrid 3: Bale, Ronaldo and Morata complete stunning turnaround|
|Inter 1 Roma 3: Nainggolan at the double in dominant display|
|Ronaldo spot on as he takes LaLiga penalty record|
|Mourinho: Fans will camp at Ibrahimovic´s house to make sure he stays!|
|Late Barca defeat leaves Simeone with sense of deja vu|
|It is not easy to keep winning – Mourinho emotional after Manchester United success|
|Mourinho: Outstanding Ibrahimovic won us the cup|
|Pogba: That´s why Ibrahimovic came here|
|Ibrahimovic hails his predictive powers after sealing EFL Cup triumph|
|He´s incredible - Carrick hails Ibrahimovic impact after EFL Cup win|
|Mourinho equals Clough and Ferguson record with EFL Cup triumph|
|Manchester United 3 Southampton 2: Ibrahimovic settles thrilling final|
|Lewandowski focused on writing his own Bayern history after Gerd Muller comparisons|
|Muller: Goals aren´t everything for me|
|Bacca goal should not have stood – Montella|
|Kane one of the top strikers in the world - hails Pochettino|
|Messi celebrates 400th win with Barcelona|
|Atletico Madrid 1 Barcelona 2: Messi leaves it late again to stun hosts|
|Leicester should have to play without a manager, blasts Mihajlovic|
|What a first half! - Record-breaking Kane lauds Tottenham display|
|Fabregas ´humbled and proud´ after 300th Premier League game|
|Sassuolo 0 AC Milan 1: Controversial Bacca penalty proves decisive|
|Zarate confirms ACL injury|
|Bayern Munich deny Eberl approach|
|Rooney on bench for EFL Cup final|
|Tottenham 4 Stoke City 0: Kane hat-trick sends Pochettino´s side second|
|Norwich City 1 Ipswich Town 1: Knudsen and Bialkowski frustrate Neil´s men|
|´No regrets´ for Ben Yedder after rejecting PSG move|
|Mignolet: Liverpool harder to stop now than with Suarez|
|O´Neill rules out taking Leicester job and questions players´ attitude|
|´Uncle´ Toure still uncertain on Manchester City future|
|Mourinho already knows next Manchester United transfer targets|
|Newcastle Jets 1 Central Coast Mariners 1: Honours even in F3 Derby|
|Half a century of Kazuyoshi Miura: Japanese legend plays on 50th birthday|
|´Criminal´ if Shaw doesn´t succeed at United - Neville|
|Kaka scores first goal in Orlando City´s new stadium|
|Conte lauds Chelsea´s milestone man Fabregas|
|Pochettino questions readiness in Tottenham´s trophy quest|
|Mata wants to extend Manchester United contract|
|Mourinho is a winner - Cantona backs United for success|
|Allegri grateful Juve control Serie A title destiny|