Having fallen behind to Miroslav Klose's first-half opener, Manolo Gabbiadini was on hand to restore parity for the holders midway through the second half, following some fine work from Gonzalo Higuain.
The result leaves the tie finely poised heading into the second leg, although Benitez will undoubtedly be confident his side can progress to the final given that Lazio have not won at San Paolo in six years.
He told Rai Sport after the game: "We saw a game with intensity and pace – the rain made it feel like the Premier League – and the players were perfect considering we have so many games at the moment.
"I said many times that we rotate the squad to maintain sharpness, which was important tonight against an intense side like Lazio and especially on a quick pitch.
"This is a strong squad. Competition between players allows us to reach these games with the right level of intensity and spurs everyone on to do better.
"I am satisfied with the team performance. We win and lose all together."
Meanwhile, Lazio boss Stefano Pioli believes his side are still in with a chance of progressing to the final, despite admitting his team will be underdogs.
"Clearly at this moment the result favours our opponents, but the second leg remains open," he told Rai Sport:
"We are satisfied with the performance, but should’ve made more of the chances we created to score more.
"We will go to the San Paolo to score a goal, which is our attitude in every game anyway, and have a month to prepare.
"It is a tough fixture, but I believe we have the quality and characteristics to qualify. Of course we wanted a better result tonight, but we have the potential to score in Naples.
"We believe in our chances and tonight’s performance should give our players more belief too."
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