AC Milan director Massimiliano Mirabelli blasted the players after their home defeat to Benevento.
Pietro Iemmello proved Benevento's matchwinner.
“We must apologise to the fans for this defeat. With all due respect to Benevento, Milan should not have lost this game. There was fatigue and very little concentration," director of sport Mirabelli told Mediaset Premium.
“It wasn't an issue of tactics, as you can win games if you put your soul into it. We mustn't lose our heads. We know the limitations and the potential of this squad.
“We are ashamed of this performance, but mustn't let ourselves become distraught. When you change so many players in a season, these things can happen. We knew that it'd take time to build a whole new time and it's not always possible to achieve your objectives straight away.
“We have clear ideas on what to do next on the transfer market and know where we have to intervene."