In a meeting of new managerial appointments, Eusebio Di Francesco and Rudi Garcia - both veterans of Serie A - came into the season with contrasting agendas.
Clear pre-match favourites Napoli were aiming to become only the third different side this century to defend the Scudetto. But their title defence suffered the ultimate false start when summer signing Jens Cajuste gave away a penalty for an overzealous challenge with no real danger on goal.
Abdou Harroui coolly stepped up, and using his vital Serie A experience in a team of league debutants, sent Alex Meret the wrong way to stun the champions.
As comeback kings last season, Napoli inevitably regrouped. And it was Politano who took the initiative, with his thunderous left-footed effort from Giacomo Raspadori’s rebound dragging the Partenopei level.
It was one-way traffic thereafter, and Raspadori himself then found the net, only for VAR to overrule for offside earlier in the move.
Napoli once again looked like the unstoppable force of 2022/23, and that feeling only strengthened just before the break, when their 26-goal top gun Osimhen fired a blistering first-time effort into the roof of the net after a strong run from Giovanni Di Lorenzo down the right.
Albeit in the second tier, Stadio Benito Stirpe was a fortress last season, with the Canaries losing only two in front of the home fans in the entire campaign. And even with the drastic step up in opposition, they would not surrender that easily.
Indeed, Jaime Baez had Meret panicking with a long-range freekick that looked destined to ripple the net, before crashing off the woodwork.
Osimhen then showed how it’s done, clinching his second strike of the evening after beating the offside trap and rolling past Stefano Turati in a one-on-one he was never going to lose.
With Napoli celebrating an 18th goal in just five meetings between the sides, Garcia’s unbeaten six-game personal record against Di Francesco was secure.
Despite missing Khvicha Kvaratskhelia through injury, Napoli looked as potent as ever, leaving Frosinone under no illusions as to what it will take to avoid an immediate Serie B return at the third time of asking.
Flashscore Player of the Match: Victor Osimhen (Napoli)
Elsewhere in Serie A:
Verona snatched a 1-0 win away at Empoli thanks to a 75th-minute goal from Federico Bonazzoli to start their league campaign well.
