Milan s hopes of Champions League were qualification were hit by a 2-1 home defeat to Sassuolo in their first match since playing a part in European football s remarkable Super League saga.
The Rossoneri were among 12 elite clubs signed up to play in a controversial new continental competition until England s big six backed out on Tuesday and prompted its collapse.
Milan have not played in the Champions League the tournament the lucrative Super League sought to rival since 2013-14 and have work to do to clinch the top-four finish that would end that wait, barring any UEFA sanctions.
Substitute Giacomo Raspadori s quickfire late double, after a superb Hakan Calhanoglu opener, leaves the second-placed side still well within reach for Napoli in fifth, six points ahead but with a game in hand to come for the Partenopei.
1 Giacomo is the first player able to score a brace as substitute vs AC Milan in Serie A in the 3 points for a win era (since 1994/95). Flight.
— OptaPaolo (@OptaPaolo)
Milan only confirmed their own withdrawal from the breakaway competition five hours before kick-off and they were then a little slow to get going at San Siro, grateful to goalkeeper Gianluigi Donnarumma when he blocked from Jeremie Boga, who had sold Fikayo Tomori with a dummy.
Calhanoglu supplied the breakthrough strike on the half-hour, though, as he shaped a gorgeous finish into the top-right corner from the left side of the penalty area.
Sassuolo keeper Andrea Consigli repelled fierce drives from Alexis Saelemaekers and Calhanoglu following the interval, before an inspired substitution turned the game on its head.
Raspadori was introduced on 64 minutes and stabbed in the equaliser 12 minutes later, reacting fastest when Jeremy Toljan s shot was deflected into the middle of the six-yard box.
The 21-year-old forward only had to wait another seven minutes for his decisive second, turning away from Tomori in the area and finishing via the post.
Milan might have fallen further behind if not for Donnarumma, who saved from Lukas Haraslin and scooped clear the loose ball, but there was no reprieve for the Rossoneri as Raspadori, of all people, blocked Samu Castillejo s late indirect free-kick.
What does it mean? Super League sides suffering
Off-field actions among a dozen elite clubs have prompted ridicule, and the players are struggling to make amends on the pitch right now.
After draws for Liverpool on Monday and Chelsea on Tuesday, Milan were the next Super League side in action and they could not even claim a point.
The title is certainly now gone, with Inter nine clear with a game in hand, but Champions League football next term despite the events of the past few days should yet provide Milan some consolation.
Super sub Raspadori
The Sassuolo man had some impact in his 36 minutes on the pitch. The striker scored with his only two shots and also created two chances.
Crucially, he came up with a single huge block at the other end, too, ensuring his goals gave Sassuolo a first win in 10 Serie A meetings with Milan.
Tough Tomori outing
Centre-back Tomori has largely impressed since signing for Milan on loan from Chelsea, but this was not one of his better displays.
Although he made a tackle, four clearances and two blocks, Tomori was too often exploited on a busy evening, dribbled past for just the third time in Serie A for the winner.
What s next?
Milan do not play again until Monday, a mammoth match at sixth-place Lazio. Sassuolo welcome Sampdoria on Saturday.
