Three-time European champion Inter was the last Italian club to lift the trophy, when it won an unprecedented treble of the league, Italian Cup and Champions League under José Mourinho in 2010.
AC Milan finished Serie A 2021-22 season with 86 points, two more than city rivals and defending champions Inter.
The win helped AC Milna teke a two-point lead over city rivals Inter Milan after the defending champions beat Empoli 4-2 on Friday.
Defending champion AC Milan was beaten 4-0 at Lazio in Serie A on Tuesday to extend the Rossoneri’s winless streak to five matches across all competitions.
AC Milan need just a point from their final match to secure first Serie A title since 2011. AC Milan play Sassuolo in the final round next weekend.
Following errors by Inter and Napoli goalkeepers in recent matches, AC Milan were the beneficiary of a mistake by Fiorentina goalie.
Cristiano Ronaldo converted a penalty becoming the first man to score a goal in five World Cups.