Wenger confirmed in his press conference on Thursday morning that Mustafi would miss around 4-6 weeks, which wasn't as bad as first feared, but still means that it is unlikely that he will feature in any of Arsenal's games before the next global break.
The Arsenal defender's injury is yet another example of why many club managers hold their breath for the duration of each and every worldwide break, hoping their players return as they left.
'He didn't play in their first game and we lost him in the second - we have to cope with that now'.
Arsenal will be hoping to extend their winning run after defeating Brighton by a 2-0 score-line in their last game before the worldwide break.
Now 32, Koscielny is one of the most experienced players in Arsene Wenger's squad, too. I will decide that tomorrow.
Midfield: Sead Kolasinac is a minor doubt with a hip injury but the Bosnian worldwide is expected to be available while Hector Bellerin should keep his place on the opposite flank. At the moment, he's not available. He worked quite hard physically, he looks like he is capable of playing if he survives the test.
The boost means Wenger could well be presented with a selection headache for the attacking side of his team for Saturday's late kick-off. If Kolasinac is out then and Monreal has to play left-back then Calum Chambers is likely to step into the back three. "But he trained on his own and the first signs are positive, so we chose to give him a test tomorrow", he added.
Silva said: "Tomorrow we will do the first session after he's back this afternoon". Wenger did however have good news regarding Mesut Ozil.