Petr Cech injured his groin after coming up for a late Arsenal corner against Swansea, while Laurent Koscielny will also miss the derby with Tottenham.
In the final minute of their 2-1 home defeat to Swansea, Cech went up for a corner. While up there, he injured his groin and will now miss the crucial north London derby.
A despondent Wenger also confirmed that Koscielny would also miss the game against Tottenham after he injured his calf.
“Petr Cech struggled. He had a groin problem before the game, and he struggled on a little bit tonight,” Wenger said.
“He will not play on Saturday.
“I trust completely [David] Ospina, I have no problem with that.
“It’s a muscular problem, a calf problem. I don’t know how long he will be out.
“Koscielny has a calf problem as well. He will not play on Saturday as well.”