The midfielder started the game at the Etihad but did not return for the second half, replaced by Albert Sambi Lokonga as the Gunners went on to lose 1-0 thanks to a Nathan Ake goal.
It was not clear at the time what had happened to the Ghanaian, but it has since been confirmed that he felt pain in his ribs and Arsenal boss Mikel Arteta says he will be sent for a scan.
‘He felt something and we didn’t want to take any risks, so he could not continue,’ said Arteta.
‘He had some discomfort and it was getting worse and worse, so he could not continue. He wasn’t comfortable to continue.
‘Obviously tomorrow, the day after he will have to have an MRI scan and see what he has.’
Partey has been in fine form for the Gunners so far this season and his injury will be a huge concern for Arteta as they continue with their challenge for the Premier League title.
However, a replacement could be on the way shortly after a £60m bid was made for Brighton’s Moises Caicedo.
The Seagulls are thought to want more like £80m for the Ecuadorian, but he has confirmed that he wants to leave the club so a deal could be in the offing before the transfer window shuts next week.
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