And he has begun his second spell in the Sere A with a major statement of intent, guiding Napoli to a crushing 3-0 victory over Bologna at the weekend.
There may have been just one round of matches in Italy so far, but Napoli are top of the table.
And heavy Scudetto favourites Juventus best take heed, as the Partenopei are now led by a manager who twice broke the Barcelona-Real Madrid duopoly with Valencia.
Benitez wisely spent the money Napoli banked from selling Edinson Cavani to PSG, and is confident that his new team’s opening day vigour was no flash in the pan.
"I'm not surprised at the result today. I saw the team throughout the week and they played very well," he said.
"We don't think about Juventus at this stage, we only think about ourselves. We changed a few players from last season's team but they did just fine and now we can look ahead."
And according to Hamsik, there is major belief at Estadio San Paolo this season that Napoli have the firepower to go all the way.
"Today was a game we wanted to win to start the season on the right foot. We didn't read anything into it, it means nothing," he said.
"It will be difficult for Gonzalo Higuain to score the same number of goals as Edinson Cavani but we have to help him and try and score 10 goals apiece.
"Me, Callejon, (Dries) Mertens, (Goran) Pandev can all score goals. We are more competitive than last season and that is good for Napoli."