The game at San Siro will take place less than 48 hours after Italian former prime minister Silvio Berlusconi finalised his sale of AC Milan to a Chinese-led consortium on Thursday for 740 million euros ($788 million).
Vincenzo Montella's side stay in sixth place with the draw, two points above Inter, who are now without a win in four matches.
Milan kept pressing, however, and were rewarded for their perseverance when central defender Alessio Romagnoli volleying home Suso's cross in the 83rd minute to set up a grandstand finish.
A corner with the last kick of the game saw Cristian Zapata acrobatically turn on the underside of the bar and goal-line technology confirmed it had crossed over.
"It's not true to say that there was no reaction in the second half with Crotone, the team reacted and we didn't deserve to lose".
The Rossoneri supporters also displayed another banner at the start of the first half, with the words: "We hope to see seriousness, commitment and presence".
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Inter doubled its lead a minute from halftime as Ivan Perisic won the ball in midfield, played a one-two with Icardi and then raced down the left flank before pulling back from the byline for the Argentine to tap in at the near post. Atalanta travel to title-chasing Roma, who are six points behind leaders Juventus, later in the day.
Stefano Pioli stressed that their duty is to do everything they can to win the derby. "I think with a little bit more concentration we'd be going home with the three points".
There was not even time for the game to restart.
The Nerazzurri almost snatched a third when a rapid counter released Icardi down the left wing before the striker found Perisic with a slide-rule pass but the winger's first-time effort was too tame to trouble Donnarumma.
Milan got back in the match in the 66th minute when Romagnoli volleyed in Suso's cross from close range, giving Milan new belief.
And Zapata sent the Rossoneri faithful into raptures in the past seconds of the match, directing the ball off the bar and definitely within the line following Manuel Locatelli's corner, with all the referee blowing for full time just as the Milan parties started.