Arsenal will qualify if they avoid defeat against a Napoli side who, in all probability, need a victory on Wednesday to progress from Group F.
The Italian side sit third, level on points with second-placed Borussia Dortmund and three behind Arsenal, but with Jurgen Klopp's charges facing winless Marseille, the onus is on Napoli to earn the win.
A 3-0 triumph would take Rafael Benitez's men above their visitors but Wenger believes Arsenal are in the right frame of mind to book a spot in the last 16.
"The attitude of the players is focused and ambitious. That pleases me very much," the Frenchman said.
"We will play our usual game and try to take control of the ball.
"Tomorrow (Wednesday's game) is a decider in the Champions League, that is for sure."
Wenger also confirmed that Bacary Sagna and Lukas Podoloski (both hamstring) have not travelled to Naples.
