Raheem Sterlingâs first-half goal was enough to secure all three points for Pep Guardiolaâs side at the Etihad stadium.
Partey was named on the bench, as Arsenal manager Mikel Arteta preferred the midfield pairing of Granit Xhaka and Dani Ceballos.
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The Ghanaian was, however, introduced into the game in the 83rd minute, replacing Xhaka in the middle of the park.
The 27-year-old didnât influence the game much, having had just a single full training with his Arsenal teammates.
He was lively, though, and ended the game with a yellow-card after committing a foul in the dying seconds.
"I think we have to respect that process and that timing for him because he only trained for a day really and thereâs a lot of new information and different game models for him to understand, and we have to respect that,â Arteta said after the game.
"But I think when he came on he looked good."
Partey will hope to be handed his first start in an Arsenal shirt when they Gunners begin their Europa League campaign this week.