Napoli lost ground in the Serie A title race as they were held to a 1-1 draw away at Juventus on Thursday night.
Juve dominated early on and should have gone ahead when Weston McKennie met Federico Bernardeschi's corner, but the American could only nod wide from the centre of the box.
Somewhat against the run of play it was the visitors who took the lead as Dries Mertens collected Matteo Politano's layoff to fire beyond both Wojciech Szczesny and the retreating Matthijs de Ligt.
Napoli looked to have seize the initiative but couldn't build on their advantage and were made to pay when Federico Chiesa shot in from outside the box via a Stanislav Lobotka deflection.
Napoli are now six points behind Serie A leaders Inter, who had their Thursday game postponed, and five behind Milan who beat Roma 3-1. Meanwhile, Juve are down in fifth, three points behind fourth place Atalanta.
Juventus player ratings
1. Goalkeeper & defenders
Wojciech Szczesny (GK) - 6/10 - Had a few routine saves to make throughout. Got a finger on Mertens' strike which stopped De Ligt being able to clear it, though it's hard to attach any blame to either for the mix-up.
Juan Cuadrado (RB) - 6/10 - With Juve struggling to create in midfield, Cuadrado was one of their main hopes in the attacking third. Buzzed around on the right and was always an outlet, but couldn't make a massive impact.
Daniele Rugani (CB) - 7/10 - With Giorgio Chiellini and Leonardo Bonucci out, Rugani was given a rare start and did reasonably well. Chiellini and Bonucci's absences weren't that noticeable, which says enough.
Matthijs de Ligt (CB) - 7/10 - Retreated onto the line but the slightest touch from Szczesny diverted Mertens' shot out of his path. Positionally he was excellent and never shy of getting on the ball.
Alex Sandro (LB) - 5/10 - Booked for hacking down Politano. Once seen as one of the more threatening full backs in European football but couldn't muster up anything of note here.
Manuel Locatelli (CM) - 7/10 - In a field of dodgy and stodgy Juve midfielders, Locatelli is one of the bright sparks. More progressive and creative than his colleagues, though it didn't all come off.
Weston McKennie (CM) - 5/10 - Missed an absolutely golden chance to open the scoring, heading wide with the goal at his mercy.
Adrien Rabiot (CM) - N/A - No idea what he brings to this Juve team. No creativity, no defensive stability, no attacking threat.
Federico Bernardeschi (RW) - 4/10 - Cut inside and overran the ball on a few occasions in the first half. Had been in hot form but that was extinguished on Thursday night.
Alvaro Morata (ST) - 4/10 - Passing was slopping when precision was needed and his shooting was off.
Federico Chiesa (LW) - 9/10 - Looked sharp in the opening exchanges, seeing a shot blocked before firing just wide. Dragged Juve back into the contest courtesy of his deflected goal.
Paulo Dybala (AM) - 7/10 - Brought a save from Ospina moments after coming on. Lifted Juve's tempo with his introduction.
Rodrigo Bentancur (CM) - 5/10
Moise Kean (ST) - 5/10
Mattia De Sciglio (LB) - 5/10
Dejan Kulusevski (LW) - 5/10
Napoli player ratings
5. Goalkeeper & defenders
David Ospina (GK) - 7/10 - Made a few sharp stops and was an assured presence at the back.
Giovanni Di Lorenzo (RB) - 6/10 - Got a good block in to deny Chiesa. Decent on the right but did lose Chiesa on a few occasions.
Amir Rrahmani (CB) - 7/10 - Repelled a lot of what Juve threw at his backline. Very steady.
Juan Jesus (CB) - 7/10 - Made some important blocks and was rarely caught out of position. Hardly Napoli's first choice centre-back but this performance would have encouraged manager Luciano Spalletti.
Faouzi Ghoulam (LB) - 6/10 - Enjoyed a nice amount of space to explore in the first half.
Diego Demme (CM) - 6/10 - The three of Demme, Lobotka and Zielinksi worked well against Juve's muddled trio. Demme used the ball nicely but was also booked for dissent.
Stanislav Lobotka (CM) - 7/10 - Provided some nice balance to Napoli's midfield. Unlucky with the deflection for Chiesa's goal but was solid apart from that.
Piotr Zielinski (AM) - 6/10 - Buzzed around behind the front three nicely. Tested Szczesny with a fierce drive which was a little too central. Influence waned in the second half.
Matteo Politano (RW) - 6/10 - Drifted infield nicely before assisting Mertens. Brought off for Elmas in the second half.
Dries Mertens (ST) - 7/10 - Stayed composed to rattle in the opener. Got a lot of shots away but was often repelled by Szczesny.
Lorenzo Insigne (LW) - 8/10 - Was frequently the free man on the left. Brought a decent save from Szczesny from a tight angle. Knitted Napoli's attacking play together excellently.
Eljif Elmas (RW) - 5/10
Andrea Petagna (ST) - N/A
Alessandro Zanoli (RB) - N/A