Antonio Conte suffered an embarrassing Serie A debut as Napoli boss on Sunday after his new team crashed to a 3-0 defeat at Verona, while last season's surprise package Bologna were held to a 1-1 draw by Udinese.
Verona new boys Dailon Livramento and Daniel Mosquera were on target in the second half at the Stadio Marcantonio Bentegodi, giving Conte a nightmare league start in charge of his new club.
Conte on Saturday described this season as "year zero" after Napoli finished 10th as defending champions in their previous disastrous campaign in which they went through three different coaches.
The 55-year-old also warned against heightened expectations from fans as he waits on reinforcements while Victor Osimhen, the star of the 2023 title triumph, has been frozen out for pushing for a transfer.
And although Napoli were comfortably the better team in the first half, the loss of talisman Khvicha Kvaratskhelia to injury just before the break proved crucial.
Kvaratskhelia was hurt by Pawel Dawidowicz after a last-ditch Jackson Tchatchoua tackle denied the Georgian star a chance to open the scoring.
With Kvaratskhelia off, Napoli had much less cutting edge and Verona took the lead when Livramento neatly guided home Darko Lazovic's pinpoint cross four minutes after halftime.
Andre-Frank Zambo Anguissa came closest to drawing Napoli level when his powerful effort crashed out off the crossbar on the hour mark.
Mosquera secured the points with a debut goal of his own 15 minutes later after chaos in midfield ended with the Colombian bursting through and confidently rolling home past Alex Meret.
And Mosquera made the scoreline even more embarrassing for Napoli and Conte in stoppage time when left all alone to tap in Lazovic's low pass.
BOLOGNA AND UDINESE SHARE SPOILS
Bologna were also playing their first match under a new coach in Vincenzo Italiano, who was denied a win by Lautaro Giannetti's 68th-minute header for Udinese.
Argentine Giannetti struck seconds after Bologna goalkeeper Lukasz Skorupski saved Florian Thauvin's penalty, denying Bologna who deservedly took the lead in the 57th minute through a Riccardo Orsolini spot-kick.
Although the draw is a disappointing result Bologna played with the same verve as they did last season when under Thiago Motta they qualified for the modern Champions League for the first time in their history.
Later capital city rivals Roma and Lazio get their campaigns underway with respective clashes at Cagliari and with promoted Venezia.