"Almunia will play and I have decided to stick with the same team and keep the continuity going," Wenger said at his pre-match news conference on Friday.
"In my opinion we have three world class keepers and only one of them can play. I have got 25 players in the squad and they all expect to play."
"The player (Lehmann) is disappointed but there is a lot of competition for places. He is an intelligent guy and knows what he has to do," added Wenger.
"Jens is a world class keeper but I had to make the choice for the continuity of the side."
Lehmann was expected to return after recovering from Achilles and elbow injuries, having played for Germany against Ireland in a Euro 2008 qualifier last week.