The 25-year-old was substituted just ten minutes into the game at the Allianz Arena after going down unchallenged with an apparent muscle injury.
Saka was replaced by Eberechi Eze, who went on to score the opener for Arsenal just 15 minutes after coming on.
Speaking to TNT Sports after the game, Arteta praised his side’s performance and gave a brief update on Saka.
"That is one of the highest levels we played. Two teams who wanted to press each other and wanted to attack and wanted to play. It was a fascinating game," he said.
"We started the game incredibly well, we were so dominant. Then we had to adapt without Saka. In the second half the game was a bit even and they scored the goals and we had to react, which we did.
“We scored and we had the chance to win it too. That is the level."
On Saka's injury: "They are a bit concerned. A player who has to come off with a really sharp pain is never good news but we have to wait and see."