When Edinson Cavani latched onto Goran Pandev's threaded pass to net after just four minutes, the suspicion that this game was going to be pure, unbridled fun was almost confirmed. But, aside from conceding, AS Roma had made a worryingly disappointing start to the match.
Zeman would have been content that his side had neglected to defend at all in the opening moments, but unfortunately they seemed to have left their attacking creativity in the capital too. Instead it was Mazzarri's men who made the exciting, high-tempo offensive start, with Edinson Cavani practically pirouetting in delight at the space which he was finding in behind the giallorossi back four.
They defended well too early on, staying compact and disciplined. Swiss midfield duo Gökhan Inler and Valon Behrami patrolled and probed with stereotypical precision (whilst nibbling cheese and chocolate in the breaks in play), with Roma looking a little laboured in comparison.
However, as the half worse on the visitors looked more dangerous, and had Mattia Destro had his shooting boots on, they would have been leading -- rather than losing -- at the break. Destro stabbed the ball straight at Morgan De Sanctis after half-an-hour in Roma's first real chance, before stroking the ball straight to De Sanctis' right moments later, with a shot so tame it looked like a keeper's warm-up drill.
Miralem Pjanić hit the ball with a little more anger, though his fierce, dipping shot shortly before half time was tipped over by the Italian international who ensured his side maintained their one goal advantage going into the break.
It was an advantage which was doubled three minutes into the restart, when Roma's hard work late in the first half was entirely undone by Edinson Cavani's second, which was hit on the turn and squeezed in past Uruguayan goalkeeper Mauro Goicoechea.
It could have been three soon after when Cavani turned provider for Marek Hamšík, slipping him through from the half-way line in a classic Napoli counter-attack. But, the Slovak rounded Goicoechea only to overrun the ball, and the chance came to nothing.
Roma still threatened, though Destro's hat-trick of bad misses culminated in the howler to rule them all. Francesco Totti's lofted pass found the ex-Siena striker through on goal, though under pressure from Alessandro Gamberini he contrived to volley wide from point-blank range before being hauled off to make way for Pablo Osvaldo.
Michael Bradley picked up where Destro had left off by missing an open goal once De Sanctis had smartly stopped an Erik Lamela shot, before their profligacy was finally punished. Some unimpressive defending saw Cavani unmarked from a corner, with the outcome rather predictable, as the Uruguayan sealed his hat-trick and 16th goal of the season.
Substitute Osvaldo pulled one back inside the final 20 minutes, but it was too little, too late. The petulant Miralem Pjanić was ejected for a second yellow before intelligently deciding to mope off the field as slowly as possible with his side chasing the game. Napoli capitalised as Christian Maggio eventually added a fourth after converting his initial parried effort, laying the icing on the metaphorical cake.
The victory sees Napoli move up to third place in the table, now a mere seven points behind leaders Juventus, and five ahead of sixth-placed Roma.
Napoli (3-4-1-2): Morgan De Sanctis; Alessandro Gamberini, Miguel Britos, Hugo Campagnaro; Juan Zúñiga, Gökhan Inler (Blerim Dzemaili 65), Valon Behrami, Christian Maggio; Marek Hamsik (Lorenzo Insigne 88); Edinson Cavani, Goran Pandev (Giandomenico Mesto 81)
Roma (4-3-3): Mauro Goicoechea; Federico Balzaretti, Leandro Castan, Nicolas Burdisso, Ivan Piris (Alessandro Florenzi 82); Miralem Pjanić, Daniele De Rossi, Michael Bradley; Francesco Totti, Mattia Destro (Pablo Osvaldo 62), Erik Lamela
Goals: Cavani 4, 48, 70 (N) Osvaldo 73 (R) Maggio 90 (N)
Red cards: Pjanić 75 (R)