Napoli accrued 12 points from their six Group F games in Europe, but it was not enough to put them above Arsenal or Borussia Dortmund, although they returned to league action with a second win in three matches at the Stadio San Paolo.
Goals from Gonzalo Higuain, Dries Mertens, Blerim Dzemaili and Jose Callejon sealed the points for Benitez's side and moved them to within two points of second-placed Roma, who play Milan on Monday.
The Spaniard was pleased with the reaction from his side but was quick to point that he expects them to get better as they look to get back amongst Serie A's table toppers.
"The Champions League exit was done with heads held very high, so I expected this performance," he told Sky Sport Italia. "Clearly it is different, we played against a great side and did very well.
"Of course we can still improve.
"The idea is to keep the ball, but at times there are mistakes and it can put the defence under pressure. These are individual matters rather than tactical ones."
Benitez was also quick to deny he saw the victory as revenge following his poor spell in charge of Inter in 2010.
"I have many friends at Inter," he added. "The facts speak for my history there and I have only joy in seeing my team win an important match."
