Juventus manager Maurizio Sarri’s return to his old club Napoli ended in defeat, although Cristiano Ronaldo extended his personal Serie A scoring run to eight games.
Juve are three points clear of Inter Milan at the top of Serie A after only their second loss of the season.
Piotr Zielinski gave Napoli the lead from close range with Lorenzo Insigne’s volley doubling their advantage.
Ronaldo scored in injury time for champions Juventus.
Sarri was booed by Napoli fans on his first game back at the club he left in 2018. He spent one season with Chelsea before moving to Juventus last summer.
He left the club on a high – leading them to a club record points tally in 2017-18 – but returned to take on a side who were 13th in Serie A after a run of one win in 12 league games.
But the Naples club, now managed by Gennaro Gattuso after sacking Carlo Ancelotti, enjoyed an impressive win over the eight-time-in-a-row Italian champions.
Juve almost equalised in injury time but Gonzalo Higuain’s bicycle kick was saved by Alex Meret.
Ronaldo’s consolation makes him the first Juve player to score in eight consecutive league games since David Trezeguet in 2005
Article courtesy of BBC Sport