Milan had opened the scoring in seven of their previous 10 league games, and it took them just 12 minutes to do so again, as Christopher Nkunku found Alexis Saelemaekers on the edge of the box.
The latter shot brilliantly into the bottom corner, but Parma came back quickly and thought they responded through ex-Milan forward Patrick Cutrone, but his goal was disallowed for offside.
Instead of suffering an equaliser, the visitors doubled their lead from the penalty spot as Abdoulaye Ndiaye made a clumsy challenge in the area, after which Rafael Leão stepped up and dispatched the spot-kick beyond Zion Suzuki’s reach.
Parma did not give up, though, and after Lautaro Valenti’s header was saved by Mike Maignan, the hosts found their first goal in seven league games just before half-time.
Sascha Britschgi passed to Adrián Bernabe, and he did the rest, curling beautifully into the top corner from the edge of the box.
Overall, 2-1 was a fair reflection of play at the interval, and though it further extended the Rossoneri’s unbeaten first-half record in the league, there were occasions where Parma gave them a fright, giving both sides something to reflect on in the dressing room.
The hosts continued their momentum into the second half as Bernabé was given another chance to score, but this time he curled over in a promising position.
Milan fans and players alike were getting more anxious by the second, and Parma finally found the equaliser just after the hour mark, as Britschgi grabbed his second assist by crossing for Enrico Del Prato to head past the onrushing Maignan.
Milan threatened to spoil the party in the latter stages, though, as Leão flicked the ball through to Christian Pulisic, who should have scored one-on-one but instead placed his effort wide.
Both teams pushed for a late winner as Mateo Pellegrino hit the woodwork with a header, before Saelemaekers rounded Suzuki only to lash horribly off target.
Parma’s winless league streak extended to four matches as the score remained level to the bitter end, but they will take encouragement from a spirited comeback, while Milan will feel disappointed despite stretching their unbeaten away league run to five games, even if they are guaranteed to go into the November international break inside the top four, after the earlier Turin derby draw.
Flashscore Man of the Match: Sascha Britschgi (Parma)