Milan survived a spirited Genoa performance to secure a 2-0 victory that saw them leapfrog Roma and Lazio into the Serie A top four.
Genoa started the livelier in the opening exchanges, in what was a bizarre atmosphere at the Stadio Luigi Ferraris, with the three o'clock kick-off meaning many supporters were unable to attend.
Christian Kouame forced Milan's Cristian Zapata to block an effort at goal after a mazy run, and in doing so overstretched, forcing the Colombian to be replaced by Andrea Conti in the 13th minute. Just after, Genoa almost got themselves in front as Davide Biraschi's curling effort was beyond the reach of Donnarumma, but narrowly over the bar.