Rade Krunic's delightful free-kick opened the scoring in the first half before Man Utd-owned full-back Diogo Dalot curled home a fantastic strike of his own after the break.
So which players stood out most on the day?
✔️ GOOD PERFORMANCE
Rade Krunic: 7.1
After winning a free-kick outside the area on the left, he curled a brilliant, dipping effort into the top corner of the net.
He formed a dominant trio in the centre of the pitch alongside Franck Kessie and Soualiho Meite.
Diogo Dalot: 7.6
However, Dalot impressed hugely on Sunday in the absence of Theo and crowned his display with a fantastic goal.
The Man Utd-owned starlet curled into the top corner to double Milan's advantage. He also boasted a game-high five interceptions.
It will be interesting to see whether he joins the Rossoneri permanently at the end of the season or returns to Old Trafford.
⭐ Soualiho Meite 7.7
Meite's career at San Siro started slowly after arriving on loan from Torino during the January transfer market.
This was his best game since joining as he put in a monstrous performance in the middle of the park.
He had the most dribbles and most recoveries on the pitch, while only Franck Kessie won more than his 14 duels. A really powerful and dominant display by Meite.