Koscielny had to come off early in the 3-0 Champions League play-off win in Turkey after taking a nasty kick to the head, giving Wenger another potential absentee he could have done without.
Bacary Sagna moved into the middle of the Gunners' defence and will most likely be there again on Saturday when they travel to Fulham because Koscielny is banned for his red card against Aston Villa.
There were fears he might have fractured his skull, but Wenger hopes the Frenchman will not be out for very long as he said: "He's like a boxer who had a hard fight the night before; lots of blood around his eye and a deep cut.
"He is suspended for Saturday anyway but let's hope he recovers for next Tuesday [against Fenerbahce]. It will be short because the cut is very deep. Hopefully it will be alright."
Wenger also had positive updates on a couple of other players and hopes his outfield options will soon be boosted, outside of any additions he can make before the transfer window closes on September 2.
"The news is quite positive at the moment," he added.
"Of course we have some players who I will need to consider because of the accumulation of the international game and then the Premier League and Champions League matches. I will have to make a deeper analysis tomorrow and on Saturday morning.
"(Ryo Miyaichi) is back in full training now. He will be involved this season in the first-team squad. Hopefully very soon because he's now getting fit.
"(Thomas Vermaelen) is out running. He's on the pitches again. But there's still a good few weeks to go for him to get his fitness. We have Nacho back and Thomas soon back so that's all good news for us."