Arsenal fullback Bacary Sagna has been ruled out for at least three weeks with an ankle injury.
"He has an ankle injury and the first news that we have is that he could be out for quite a while," said Wenger.
"I don't know [exactly] how long he will be out but I feel it will be three weeks at least. Five is the [worst case scenario].
"I have seen the injury again on tape. He wanted to kick the ball out and he twisted his ankle. That made it a bad injury."