Stefano Pioli says Milan have a "desire to restart" as they attempt to recover from their derby loss to Inter.
Milan's 3-0 defeat to the Nerazzurri left them four points adrift of their rivals at the top of the Serie A table having led the way for most of the campaign.
Pioli's men are without a win in three games in all competitions having drawn the first leg of their Europa League round-of-32 tie with Red Star Belgrade 2-2 in between losses to Spezia and Inter.
Speaking ahead of the return leg with Red Star at San Siro, Pioli said: "It is right that there were no smiles on Sunday, but we have a great desire to restart, to express ourselves at our best and to obtain excellent results.
"I see a determined and willing group, eager to return to the levels we have shown. I told the team that there are 90 days left in the championship, it could be 93 with the Europa League final if we were to be particularly good.
"These days will fly by and will be decisive days to ensure that the season can be positive, very positive or great.
"Now we have to demonstrate our qualities and our motivations on the field. The group works very well and believes in what it does.
"Matches are all different. The derby was a completely different match. Matches can change during the match, but we need to have clear playing principles that need to start the match one way and keep going all the way. We will be prepared to do it."
On the situation in the tie with Red Star, in which Milan have the edge on away goals, Pioli said: "There is a tough obstacle to overcome, we have a very slight advantage that we will have to be good at exploiting to pass this round."