Goals from Jose Callejon, Gonzalo Higuain and Jorginho secured a 5-3 aggregate win over Roma to book a final date with Fiorentina in May.
Goals from Jose Callejon, Gonzalo Higuain and a first Napoli strike for January signing Jorginho saw the Partenopei overturn a 3-2 first-leg deficit to secure a clash with Fiorentina in early May.
"It wasn't the perfect performance, but it was almost perfect," Benitez beamed at his post-match press conference. Everyone worked hard in the defensive phase and then we were able to score three great goals.
"The team showed their quality. It was difficult to win against this Roma team and to do it without conceding a goal."
Diego Maradona was in the stands at the San Paolo to watch his former club turn the tie around with two quick-fire goals early in the second half and Benitez was delighted to have won in front of the Argentina icon.
"It was easier to win with Maradona there, but let's not take credit away from these lads, as they played really well. I met Maradona some years ago, he could still be useful for us on the pitch," Benitez added.
Benitez was thrilled with the added balance his side's January investment has brought about and believes Marek Hamsik has now recaptured full fitness as the season enters a crucial stage.
"The new signings are giving us more balance," he added. "It'll take a while for Henrique to settle in, as he needs to learn the language and understand our systems of play.
"Callejon can also play as a center forward. Gokhan Inler and Jorginho work very well together in midfield and help out the defense.
"Marek Hamsik has now fully recovered and is working very hard for the team. I hope this victory will give us more confidence to take into Serie A, as Sassuolo await."