Friday was a good day for the Partenopei, who celebrated in style at the San Paolo with a 2-1 friendly victory in which Pipita Higuain netted his first goal for the club.
"It was important for us, for him and for the fans who saw his quality, even if he's still only 60 per cent fit," Benitez told Sky Sport Italia.
"There were many positive things on this day and Hamsik's contract renewal until 2018 is good for the club, the fans and all of us.
"We did many good things against Benfica, though we still have to improve and will slowly reach the right level. After all, we're still 15 days away from the start of the season.
"It's true we conceded from a set-piece yet again, but we just have to work on it and these things can happen when changing so many players.
"We just have to keep on working. The fans were spectacular and with them by our side we can do very well. I've taken a tour of the city and seen many wonderful sights, but none like the crowd at the Stadio San Paolo."
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