"It isn't a case of needing new players, rather we need to be more humble as we seemed to presume we would beat Roma," Moratti snapped.
"The Super Cup defeat will help us to get our feet back on the ground. We shouldn't think that we are good enough to win without concentrating.
"It is important that we don't think we are the best just because we won the title last season - holding the Scudetto doesn't get us a goal headstart."
He added: "Let's not exaggerate - we are at the start of the season and there are a thousand extenuating circumstances.
"Of course there were lots of things that I didn't like against Roma, but perhaps we were a bit tired and not fully charged."