Crvena travelled to Milan knowing a win was vital if they wanted to give themselves a chance of progressing to the first knockout round, but in their way was a Rossoneri outfit who also needed three points to cement their place in the play-off spots.
While the hosts had the lion’s share of possession, they struggled to create much with it. Tijjani Reijnders registered their first shot on target, but the Dutchman failed to challenge Ivan Guteša with a shot straight down the middle of goal.
Rafael Leão was next to challenge the Serbian stopper, but the latter was able to stretch his left leg out far enough to prevent the winger from opening the scoring.
Moments later, visitors gave Milan a rare scare as Andrija Maksimović’s shot from the centre of the box bounced off the bar. Gilt-edged opportunities were at a premium in the first half, as Crvena continued to do a good job at stifling the hosts' offence.
Tammy Abraham was an early substitute for the injured Álvaro Morata and nearly had an instant impact as he tried to guide a cross past Guteša, but his effort went inches wide of the post.
Shortly before half-time, AC finally found a breakthrough when a long ball from Youssouf Fofana went over the Crvena defence and found Leão, who controlled and fired past Guteša.
The visitors came out swinging in the second half as Ognjen Mimović and Timi Elšnik forced two early saves from Mike Maignan to preserve AC’s lead.
Just as it seemed like the hosts were going to see out the game, Nemanja Radonjić won the ball outside the box and, after initially hesitating, the winger smashed the ball past Maignan to level proceedings.
A big issue for AC in the second half was their inability to find the target, with an Emerson Royal shot straight at Guteša being their only one of note with six minutes left on the clock.
However, shortly after, Abraham saw the ball bounce off the crossbar and land at his feet before scrambling the ball over the line to snatch the three points.
The win for Milan sees them move up to 12th in the league phase table, with a place in the play-off round all but secured.
While progress is still mathematically possible for Crevena, this loss at the death leaves them needing to make up a five-point gap to the play-off positions with only two games left.