*Club domestic league appearances and goals, correct as of 23:09, 24 November 2024 (UTC) ‡ National team caps and goals, correct as of 15:30, 26 September 2022 (UTC)
On 9 July 2018, he signed a four-year contract with Serie B club Perugia.[2]
On 25 January 2022, Mazzocchi joined Serie A side Salernitana on loan from league rivals Venezia with a conditional obligation to buy.[3]
On 5 January 2024, Mazzocchi joined reigning Serie A champions Napoli on a permanent deal,[4][5] signing a three-and-a-half-year contract with the club.[5][6] The transfer reportedly commanded a fee of about €3 million.[6] Two days later, on his debut for the Partenopei, Mazzocchi received a straight red card just four minutes after coming on as a second-half substitute, following a VAR check, in a 3–0 league loss away to Torino.[7][8] It was the third-fastest send-off for a debuting player in the history of Serie A, behind only Rolando Bianchi and Francesco Cassata.[9]