The Rossoneri had a mixed week, suffering their first Serie A defeat of the season, yet winning away to Atletico Madrid in the Champions League. Olivier Giroud joined Fikayo Tomori, Davide Calabria, Samu Castillejo and Ante Rebic on the treatment table, but Mike Maignan made his comeback in goal way ahead of schedule, having originally been ruled out for three months after wrist surgery on October 12.
It lasted just three minutes before Gianluca Scamacca surged forward and unleashed a screamer from distance that flew into the far top corner, giving the returning Maignan no chance.
Sassuolo penalty appeals were rejected for Brahim Diaz handball, as his arm was flush to the torso.
The visitors turned the game around completely from another corner, as it was only cleared as far as Scamacca, whose shot was parried by Maignan’s leg, but only to ricochet off Simon Kjaer and back into the net from a couple of yards.
They almost capitulated completely, Maignan getting to a Giacomo Raspadori angled drive and Scamacca nodding wide.
Milan’s midfield was providing no protection, so Franck Kessie and Junior Messias were introduced at half-time.
Instead, Sassuolo extended their lead when Kessie and Sandro Tonali failed to clear, Berardi sent Romagnoli to ground with a dummy and nutmegged Maignan from a tight angle.
Kjaer’s header skimmed the far post and Theo Hernandez was fortunate to avoid a second yellow card for a row with Frattesi.
Junior Messias saw his angled drive beaten away at the near post for a corner, but it went from bad to worse with Romagnoli shown a straight red card for his rugby tackle on Gregoire Defrel on the edge of the box, after being skinned for pace.
Maignan parried a Berardi free kick to keep the scoreline down.
Milan 1-3 Sassuolo
Romagnoli 21 (M), Scamacca 24 (S), Kjaer og 33 (S), Berardi 66 (S)
Sent off: Romagnoli 76 (M)