Juventus defender Giorgio Chiellini has torn a muscle in his left knee, the club announced on Monday.
2017 SeasonAll times ET
Sarri, who made the gesture as his team arrived at the Allianz Stadium, said he had nothing against Juventus fans.
Juventus took a reactive approach and struggled to hold off Napoli's press before surrendering in the final minutes. Now the title race is on.
Juventus boss Massimiliano Allegri has targeted next Saturday's date with Inter Milan as the "decisive'' fixture in the Serie A title race.
If Napoli go on to win a historic Serie A title, Sunday night's dramatic injury-time win over Juventus will be that turning point.
Kalidou Koulibaly scored in the 89th minute to secure a dramatic 1-0 win against Juventus and cut the Old Lady's Serie A lead to a single point.
Napoli and Juventus face off in a clash of styles and philosophies on Sunday with major Serie A title implications at stake.
Just days ago, Napoli's title challenge seemed to be dead but favourable results Wednesday make Sunday's trip to Juventus the "mother of all games."
Juventus' Beppe Marotta said his club cannot afford to buy back Paul Pogba or Alvaro Morata this summer, although there may be exceptions.
Max Allegri switched the focus to Juventus' top-of-the-table clash with Napoli after the leaders were held to a 1-1 draw by Crotone on Wednesday.
Juve let two important points slip ahead of their clash against Napoli on Sunday, with Stefano Sturaro typifying the Bianconeri's lax attitude.
A much-changed Juventus saw their lead at the top of Serie A cut to four points after being held to a 1-1 draw at struggling Crotone.
Now everyone has vented, Gigi Buffon, Juventus, Real Madrid and everyone else should move past Champions League controversy and conspiracy talk.
UEFA president Aleksander Ceferin understands Juventus goalkeeper Gianluigi Buffon's frustration at getting knocked out of the Champions League.
While the officials might have overreacted in giving Gianluigi Buffon a red card in the Real Madrid match, it's time for everyone to move forward.