Simone Zaza's last-gasp goal fired Juventus to the top of the Serie A table at Napoli's expense.
The Azzurri arrived in Turin hoping to extend their two-point lead in the Scudetto race but the league's top scorer Gonzalo Higuain and his teammates failed to breach the reigning champions' defence.
Massimiliano Allegri's men toiled in their own pursuit of a goal until the 88th minute, when substitute Zaza earned a 15th straight win -- 1-0 on the night -- while ending Napoli's long run as leaders.
The southerners, who had won eight consecutive games before Saturday's encounter, must now hope Juve slip up at some point across the last 13 matches of the season.
Allegri took a calculated risk by playing three at the back while Napoli boss Maurizio Sarri fielded a formation familiar to fans who had witnessed an eight-game winning streak on the road to Turin.
Juve's ambitious approach meant they enjoyed the best of the early running with Juan Cuadrado testing Jose Reina's reflexes and Paul Pogba fizzing a free-kick just over the visitors' crossbar.
When Napoli did decide to turn up following the half-hour mark the game really sparked into life and there might well have been several goals scored before the break.
Leonardo Bonucci made a fantastic interception as Elseid Hysaj's cross sailed towards the onrushing Higuain and Gianluigi Buffon was soon repelling Raul Albiol's header at close quarters.
After Higuain came up just short on a searing pass into the box from Jose Callejon it was time for Juve to react.
Cuadrado accepted the challenge and skipped past three defenders before touching inside for Claudio Marchisio, who could only flick the ball into Reina's gloves.
The former Liverpool goalkeeper then controlled Pogba's long-range effort to call time on the first half.
Napoli almost opened the scoring in the moments following the restart. Lorenzo Insigne's movement caused chaos in the Bianconeri box but Buffon was ready to pounce when he finally pulled the trigger.
Patrice Evra fancied becoming Juve's unlikely hero and got into a good position to turn Sami Khedira's pass home at the far post -- instead, he blasted well over.
The Bianconeri came much closer shortly after the hour with Pogba setting up Paulo Dybala for a fierce shot on the turn that shaved paint off the bar.
Napoli kept their cool under increasing pressure, however, and their dominance in midfield allowed Marek Hamsik to unleash a swerving shot that whipped over Buffon's head and out.
As time ticked away it looked as if the title rivals might have managed to cancel each other out.
To Napoli's dismay, that was not to be the case.
With two minutes left, substitute Zaza, on for Alvaro Morata midway through the second half, propelled Juve to the top of the table with a stunning left-footed finish that Reina could not reach.