Kalidou Koulibaly promised Napoli will respond after the centre-back's stoppage-time own goal handed Juventus victory in a thrilling Serie A clash on Saturday.
Carlo Ancelotti's side came from 3-0 down to level at 3-3 with nine minutes of normal time remaining only for Koulibaly to score in his own net in the second minute of injury time.
Danilo, Gonzalo Higuain and Cristiano Ronaldo put Juve in complete control only for the champions to collapse, allowing new signings Kostas Manolas and Hirving Lozano to score in the space of two minutes.
Giovanni Di Lorenzo thought he had rescued a point for the visitors in Turin before Koulibaly sliced a hopeful Juve free-kick into the top-right corner of Alex Meret's goal.
Napoli defender Koulibaly admitted he is hurting after the defeat but backed his team to show they have the mettle to recover.
"It's an own goal that hurts me because it came after an incredible comeback," he wrote on Instagram.
"I'm sorry but I have to - we have to accept it: we are strong. We showed it. We will prove it."
Koulibaly was turned brilliantly by former team-mate Higuain, who scored for the first time since returning to Juve from a loan spell at Chelsea last season.
"It was a rollercoaster," Juve striker Higuain told Sky Sport Italia. "They scored two quick goals, which can't happen. We lost control of the match and they equalised but, in the end, it's ended up like this.
"It's a really important win. We have things to improve, but we left everything out on the pitch and the reward came in the end."
Higuain has surprisingly won back a place in Juve's plans despite being deemed surplus to requirements last season and sent for a largely disappointing spell under Maurizio Sarri at Stamford Bridge.
The Argentina international insisted he wants nothing more than to stay and prove his worth again in Turin.
"I'm motivated to stay here. I love this shirt, this club, these fans. From the first second I arrived, I was determined to stay," he said.
