Arsene Wenger's side are just one point behind Group B leaders Schalke and have the chance to top the group with a positive result against their Greek opponents.
Wenger may take the opportunity to rest some players ahead of Saturday's home game with West Brom but Gervinho does not feel that will affect how they approach Tuesday night's in Athens.
"It's a bit different for us because first place of the group is still up for grabs so we do have something to play for, even if we have qualified already," he told Arsenal's official website. "Also, the manager might rotate the team and then it becomes a good opportunity for some players who don't always play to play well and they will be very motivated.
"Even if we have already qualified, we have to stay focused and humble. For the rest of the competition, it would not be good to finish the group stages with a defeat.
"Anything is possible in football. Montpellier drew in Schalke earlier in the season so they can do it at home.
"I hope Olivier (Giroud) will make a few phone calls to the manager, the president and his former team-mates to make sure they help us!
"More seriously, if Montpellier win and we don't, it will be pointless anyway. So first of all, we need to do our part of the job.
"We will stay focused on ourselves and beating Olympiakos and then we will have a look at how Montpellier are doing.
"Look at Real Madrid. They are sure to finish second (in Group D). So if you win your group, you could still face them in the last 16.
First, let's beat Olympiakos and then whoever we face in the last 16, we'll be focused on going through."