Patrick Cutrone and a Suso free kick eventually got the better of Cagliari, but Milan found it their most difficult game so far.
Vincenzo Montella’s men hadn’t conceded a single goal in their five competitive matches so far.
They had taken the lead through 19-year-old hitman Cutrone, meeting an inspired Suso assist, but then rather took their foot off the gas.
Losing control of the midfield, Milan found themselves under pressure and Joao Pedro eventually equalised.
Suso was decisive again, curling a wonderful free kick into the top corner.
Lucas Biglia and Nikola Kalinic also made their Diavolo debuts in the second half.
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