Milan got off to a quick start, dominating possession, and it seemed it would be a matter of when, not if, the Rossoneri would score.
The home side, though, had other ideas and, after weathering the early storm, they went up the other end and scored around the half-hour mark. After winning the ball in the box, Zito Luvumbo rifled a powerful shot into the roof of the net to stun the visitors.
Undeterred after falling behind, Milan continued to push forward, and their persistence paid off as they netted twice before the break.
The first arrived when Christian Pulisic’s cutback was parried by Boris Radunovic only to the feet of Noah Okafor, who rolled the ball away from the goalkeeper before firing home, and the visitors then took the lead in the 45th minute.
Radunovic was again partly to blame, parrying the ball into the path of a Milan player, and on this occasion, Fikayo Tomori was in the right place at the right time to give his side the lead.
Cagliari came out fighting at the beginning of the second half, and Luvumbo in particular was proving to be a nuisance for the Milan backline.
However, for all of their positivity going forward, Claudio Ranieri’s outfit were dealt a further setback on the hour mark as two of Milan's numerous ex-Chelsea players combined for a sublime goal.
Pulisic once again picked the ball up and drove towards the box before picking out Ruben Loftus-Cheek, who was waiting to drill into the bottom left corner from outside the area, giving Milan the space and comfort they needed.
Loftus-Cheek’s effort deflated any hopes of a Cagliari comeback and, as such, Stefano Pioli’s men were never in danger of dropping points from then on against a side who are rooted to the foot of the table with just two points from their opening six matches.
The result sees Milan move up to second, level on points with Internazionale, albeit having played a game more - after finishing well adrift of champions Napoli last term, they look on course to challenge for the Scudetto this time around.
Flashscore Man of the Match: Fikayo Tomori (AC Milan)
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Elsewhere in Serie A's early fixtures on Wednesday, Empoli secured their first victory of the 2023/24 Serie A campaign at the sixth time of asking, following a 1-0 home success over Salernitana at the Stadio Carlo Castellani.
Tommaso Baldanzi was on the scoresheet for the hosts, read the full report now.
Meanwhile, Teun Koopmeiners' first-half strike helped Atalanta to a 1-0 win over Hellas Verona at the Stadio Marcantonio Bentegodi, a third succesive victory without conceding in all competitions.
