The coaching legend feels the Catalans will struggle to turn their Champions League fortunes around in light of their recent plight.
The Catalans are currently preparing for the return of their Champions League round of 16 tie against the Rossoneri, after losing the first leg at San Siro 2-0, and Sacchi believes the Blaugrana face a difficult task to turn things around at Camp Nou.
"It's not the same brilliant Barcelona as before. They have not been in top form. It's really difficult to be always playing at such a high level and to keep up that competitive spirit," Sacchi told Marca. "Maybe Barca have gotten used to doing little to get by. In the past, they didn't have to do much as they would win anyway. In the Champions League, however, you have to pick up the pace and give it your all."
Sacchi added, "Tuesday's game will be a hard match for both teams. 2-0 is a good result for Milan. A score that obliges Barcelona to make a huge effort. Barcelona are not going to get their old form back from one day to the next as if by magic. They must try to frighten their rival. If they can do that, they will have a real chance of getting through to the next round."