Friday marked the 40th anniversary of the first cinepanettone – a genre of comedy movie released in Italy around Christmas-time each year. Vacanze di Natale was produced by Aurelio De Laurentiis, the man who would go on to become president of Napoli 21 years later. The story goes that he was unimpressed at first, worrying that the jokes were not funny enough, but its lampooning of Italy’s nouveaux riche struck a chord. A tradition was born.

De Laurentiis was the one throwing money around this weekend, signing Victor Osimhen to a new contract worth €10m per year after tax. It theoretically ties the Nigerian to Napoli until 2026, though a reported €130m release clause would not put him out of reach of football’s wealthier buyers.

In any case, it was a welcome piece of good news for a club that won Serie A for the first time in 33 years this spring but whose fortunes have taken a sharp downturn since. Napoli’s title defence has collapsed before Christmas and on Tuesday they were humiliated in the Coppa Italia, losing 4-0 at home to Frosinone.

In an interview with the Corriere dello Sport on Friday, De Laurentiis expressed regret over his decision to hire Rudi Garcia as manager in the summer. Luciano Spalletti had walked away after winning the Scudetto, and finding a replacement was always going to be tricky.

De Laurentiis told the newspaper that his first choice, Thiago Motta, turned the job down because he saw only downsides. The best he could hope for was to repeat another man’s achievements. If he failed, he would be lumbered with unfavourable comparisons.

Luis Enrique was the next choice but, according to the owner, wanted too much money. Two or three others were approached, including Julian Nagelsmann, before De Laurentiis landed on Garcia, “who had two second-place finishes in Italy [at Roma, in 2014 and 2015] with turbulent changing rooms, full of high-level players.”

“I realised Garcia was not the right choice on the day I presented him at Capodimonte,” continued De Laurentiis. “I should have made a coup de theatre and said: ‘I’ve presented him to you but now he is going’. Because someone who arrives and says: ‘I don’t know Napoli, I’ve never watched a match … I should have understood. Instead, I laughed it off. The fact is he repeated it on other occasions.”

Garcia’s introductory press conference was indeed a jarring experience. Journalists were shocked at the time by the Frenchman’s failure to acknowledge Spalletti’s achievements. But Garcia has been gone now for six weeks – fired on 14 November. You would be hard-pressed to make an argument that things have got better since.

His replacement, Walter Mazzarri, had managed Napoli before, steering them to third place in 2011 and second in 2012. Like the recurring stars of those cinepanettoni, his role was not to thrill audiences but to reassure them that we were back on familiar ground. Nobody expected him to win any prizes, just to repeat the lines that had made them smile before.

Only, football does not work that way. After a 2-0 defeat to Roma on Saturday night, Mazzarri has lost five out of eight games in charge. This one might have ended differently if it were not for a pair of second-half red cards. Matteo Politano was first to go after kicking out at Nicola Zalewski. The Roma player’s reaction was theatrical, and Mazzarri would lament how opponents had been grabbing Politano’s shirt throughout a match that was bad-tempered from the start. But this was still needless self-harm.

The game was goalless when Politano went off, but not for much longer. Lorenzo Pellegrini made the most of a bobbling ball inside the Napoli box, swivelling to hook a finish beyond Alex Meret.

Osimhen was then sent off for a double booking. He reacted furiously, accusing Stephan El Shaarawy of diving. It was unclear on the replays how much contact there had been, but Osimhen was playing with fire, applying pressure from behind to disrupt a Roma counter-attack in a match where referee Andrea Colombo had been quick to get his cards out all night.

Napoli played some of the final minutes on eight players, the substitute Natan receiving treatment to a shoulder injury. Those still on the pitch showed impressive resolve, pushing for an equaliser even into the sixth minute of injury time. But when a final attack broke down inside the Roma area, the hosts countered and secured the points with a goal from Romelu Lukaku.

Any assessment of Mazzarri’s work should acknowledge that he has faced an especially punishing run of fixtures. His seven games in charge before Saturday had included visits to Real Madrid, Juventus and Atalanta, as well as a home match against Inter.

Still, the question of whether Napoli have done any better with him than they would have under Garcia hangs in the air. The Frenchman is not missed in Naples, and nobody is arguing that the team were on a good path under his leadership, but it is still true that he lost fewer times during his 16-game tenure than Mazzarri has in just eight.

There is no suggestion that De Laurentiis is considering another change just yet. He did tell the Corriere dello Sport that he intends to strengthen the playing squad in January, adding “at least three” new players. “I need to reinforce the defence with a centre-back and a left-back to support [Giovanni] Di Lorenzo,” he said. “And then I need to get a midfielder, or maybe two.”

The use of the first-person was not casual. De Laurentiis is running this production, in better and in worse. At times, indeed, it can seem that his missteps are driven by a reluctance to share the credit for Napoli’s successes with anyone else.

His failure to acknowledge what an exceptional job Spalletti was doing – attempting to trigger an automatic contract extension instead of offering improved terms – was a factor in the manager’s decision to walk away. Similarly, De Laurentiis has downplayed the work that Napoli’s former sporting director, Cristiano Giuntoli, did before moving to Juventus in the summer, insisting that Khvicha Kvaratskhelia was first identified as a transfer target by his son Edoardo.

Spalletti returned to Naples earlier this month for a ceremony where he was granted honorary citizenship of the city. He greeted De Laurentiis warmly there, and thanked him for their time together, but also jokingly likened his former employer to a monster from a horror movie. “When you think the movie is over and you can finally stay in peace,” said Spalletti, “he shows up again to make you spill your drink and your popcorn.”

As usual, De Laurentiis was quick with a comeback, saying that American cinema’s only advances in the last 40 years were thanks to the horror genre. Perhaps he is right. Still, his football team’s fans would have preferred to ease into Christmas with something a little bit sweeter.