Maurizio Sarri's squad will face the defending champions Bologna in the quarter-finals, thanks to Italy winger Zaccagni scoring from a header off Nuno Tavares' corner with 10 minutes left in Rome.

Zaccagni's goal handed Milan their first loss since their defeat to Cremonese in August, leaving coach Massimiliano Allegri to focus on the Serie A title and the Italian Super Cup this season.

Milan lead Serie A on goal difference over Napoli, who defeated Cagliari in the Cup on Wednesday to also reach the quarter-finals.

Bologna continued their title defense with a 2-1 victory over Parma, secured by Santiago Castro's goal in the 89th minute.

The round of 16 will conclude in January when Roma host Torino and Fiorentina face Como.

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