Piotr Zielinski scored the opening goal of the game midway through the second half, finishing on the rebound after Wojciech Szczesny pushed Lorenzo Insigne's shot back into the danger zone.

Napoli had lost four home league games in a row but climbed to 10th in the table after Insigne volleyed in a second, Maurizio Sarri's return to Stadio San Paolo ending in Juve's second league defeat of the season. 

Cristiano Ronaldo hit a late reply but Juve missed the chance to move further ahead of nearest title rivals Inter and remain three points clear in top spot.

READ MORE