The Partenopei dropped their first points of the season with a 1-1 draw against Sassuolo and the Spaniard admitted he was not satisfied
The Partenopei had stormed to a 100 per cent start to the season, with four wins in Serie A and a 2-1 triumph over last year's Champions League runners up Borussia Dortmund in their only European clash this campaign.
However, the side that were beaten 7-0 by Inter at the weekend shocked the Naples-based club by putting up a resilient fight to earn a point at the Stadio San Paolo, leaving Benitez dissatisfied but not fearful of a drop in form.
"I have faith in the squad and it’s only natural that we won’t win all of the games," he told Sky Sport. "We played well, but so did Sassuolo. I think the result had more to do with Sassuolo’s performance than ours.
"We have to work on some things in training, such as how quickly we moved the ball, but I was pleased with our effort tonight. I am not satisfied, obviously, but I am not worried either.
"We played on the same level as the other performances but, if you play every three days and face a side that lost 7-0 last time out, you risk underestimating the challenge.
"We faced a team that were organised and knew what to do, proving the 7-0 to Inter was an aberration rather than a true reflection of Sassuolo."
Napoli's next game is away to Genoa on Saturday as they look to bounce back having slipped from top of the table to second behind Roma, who have won all four of their games.