The Gunners star was substituted after only 34 minutes during his side's 2-1 defeat to Lens in the Champions League on Tuesday.
Saka appeared to be hobbling as he walked around before sitting down off the ball and asking for treatment.
He was then replaced by Fabio Vieira and his withdrawal led to instant concerns over whether he will be fit enough to feature on Sunday…
Will Bukayo Saka be fit to face Man City?
Saka is a huge doubt for Arsenal's game against Man City this Sunday afternoon.
There has not yet been a concrete update on his fitness, however, Arteta has described the injury as 'a worry'.
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The winger had limped off in both games before the Gunners' trip to Lens but Arteta still decided to start his 'Starboy' in Europe.
That gamble didn't pay off and the Spaniard gave an update on Saka post-match.
Asked whether he regretted starting the England international, he said: "No. It was a knock that he had the other day and he was perfectly fine.
"It was a back-heel, an action that can produce that kind of injury.
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"Let's see what the extent of it is and afterwards it's too late. The last few were more knocks than anything else.
"He hasn't really missed games. We gave him a break against Brentford (in the Carabao Cup) last week and that was all.
"He tried to backheel a ball in the first half and felt something muscular. He felt uncomfortable to carry on so we had to take him off.
"We don't know anything more. It was big enough not to allow him to continue to play the game and that's a worry for us."
If Saka is to miss Arsenal's crucial game at the weekend, it will end his incredible streak.
He has started 87 consecutive Premier League games for the Gunners which is a club record that dates back to May 2021.
But it could well be that huge run of games that has led to his injury and he now could be absent for the biggest game of the season.