Jose Mourinho was dismisssed despite his Roma team ending Napoli's perfect start to the season on Sunday.
Napoli had won all eight of its Serie A matches but was held to a draw by Roma, hitting the woodwork twice in quick succession and having a late winner ruled out.
Roma coach Mourinho was sent to the stands for dissent nine minutes from time. His Napoli counterpart, Luciano Spalletti, was also red -arded after the final whistle as the referee judged his applause to be ironic, despite the coach's fervent protests it was genuine.
Napoli moved back top but is above AC Milan on goal difference alone after the Rossoneri beat Bologna 4-2 on Saturday. Head-to-head is the first tiebreaker in Italy if teams are level at the end of the season.
Defending champions Inter are eight points adrift of Napoli and Roma nine.
Mourinho was looking for a reaction after Roma was routed 6-1 by Norwegian team Bodo/Glimt in the Europa League midweek.
And his side almost took the lead in the 27th minute. Tammy Abraham was limping after picking up a knock but still managed to outsprint Napoli defender Amir Rrahmani, before firing wide of the right post.
Napoli should have broken the deadlock on the hour mark but Victor Osimhen hit the right post from point-blank range under pressure, and a desperate tackle by Rick Karsdorp prevented Mario Rui from turning in the rebound. Osimhen also headed the resulting corner onto the top of the bar.
Elsewhere Giovanni Simeone caught the eye, scoring all four goals against his father's former team as Hellas Verona routed Lazio 4-1.
Simeone scored two goals in each half, helped by two assists from Gianluca Caprari, who was also in inspired form.
The 26-year-old Simeone is the son of current Atletico Madrid coach Diego Simeone, who played more than 100 matches for Lazio and helped the team to the league and cup double in 2000.
Ciro Immobile had halved the deficit for Lazio at the start of the second half.
The match was also notable as the great-grandson of former Italian dictator Benito Mussolini - 18-year-old defender Romano Floriani Mussolini - was on the bench for Lazio for the first time.
Lazio slipped to eighth, while Atalanta moved a point above the capital side after it was held to a 1-1 draw by Udinese.
Atalanta was struggling with an injury crisis but looked to be heading for the win thanks to Ruslan Malinovskyi's 56th-minute strike, but Beto headed in a corner in the fourth minute of stoppage time.
Another of the chasing pack, Fiorentina, gained a comfortable 3-0 win over relegation-threatened Cagliari.
Australian Associated Press