The Nerazzurri were beaten 2-1 at the Stadio Olimpico in the first leg of the tie and Zanetti is desperate to turn things around in the return as he aims to save Inter's season with cup success.
"We want to play well against Roma on Wednesday. There's no point talking about the match against Cagliari as we can't do anything about it. Now we need to think about performing well on Wednesday," the Inter skipper told the club's official website.
He added, "We'll try to prepare in the best possible way for the match versus Roma and we hope to get a result that will see us into the final. 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."