Leonardo fears Milan may've lost their winning momentum due to the international break.
"When there is a break you always need to see the pros and cons," said the Coach.
"We'll get the answer on the field, but the essential thing is that the team steps out there with the same hunger and enthusiasm we had in our last Serie A game.
"I can see the players are really wrapped up in this campaign and I want to maintain that so we can achieve something important this season.
"Cagliari play good football and are coming off some strong results, so tomorrow is going to be a very interesting game."