Zanetti has admitted that he is "gutted" with the loss and believes that the official's decision to award a spot kick after the break cost his side dearly.
He told the club's official website: "There's no point talking about this match, we can't do anything about it, we've missed an opportunity. Now we need to think about performing well on Wednesday. The referee got the penalty decision all wrong. We're gutted about the result, and it makes you angry. But it's at times like these that we find the strength to move on and become a better team.
"We've had many matches like that this season, where we've come away empty-handed. But that's the way this season's gone. At the end of the campaign we'll look back and review everyone's performance. Then we'll begin to prepare for next season as we always do."
"Now we'll try to prepare in the best possible way for Wednesday. We hope to get a result that will see us into the final. Where will I play? We'll see what the coach thinks, all that's important is getting our preparation right."
Inter are back in action on Wednesday when they face Roma in a Coppa Italia semi-final second-leg tie.