The Rossoneri's "downward spiral" continued as they were beaten by the struggling side and have not won in six games, leaving the coach embarrassed
AC Milan boss Gennaro Gattuso slammed his side's lack of spirit while sporting director Massimo Mirabelli was left "ashamed" by the shock 1-0 home loss to bottom-placed Benevento.
Pietro Iemmello's calm first-half strike condemned Milan to a sixth successive Serie A match without a win, a run that leaves them vulnerable in sixth and at risk of missing out on a Europa League qualifying spot.
Benevento had substitute Cheick Diabate sent off for a second yellow in the 80th minute, but the rank outsiders held firm to secure their first top-flight away victory in a result that mirrored the teams' 2-2 draw in December, which marked Gattuso's maiden match in charge of Milan.