Arsenal lost Declan Rice to injury at half-time in the north London derby against Tottenham on Sunday.
The England midfielder was surprisingly taken off at the break and replaced by Jorginho for the second half.
Rice, who left West Ham to join Arsenal for an initial £100 million in the summer, was later seen with his calf strapped on the Gunners bench.
After an entertaining first half had finished 1-1, Arsenal retook the lead early in the second period after Cristian Romero was penalised for handball following a VAR check and Bukayo Saka curled a penalty straight down the middle to make it 2-1 after 54 minutes.
But straight from the restart, Jorginho got the ball stuck under his feet and was dispossessed by James Maddison, who set up Son Heung-min for his second of the game.
Arsenal also made another change at the break as manager Mikel Arteta sent on Kai Havertz for Fabio Vieira.
Both Arsenal and Spurs came into this fixture unbeaten on 13 points apiece, with four wins and a draw each from their opening five games in the Premier League this season.
More Arsenal stories
Arsenal manager Mikel Arteta has revealed Aaron Ramsdale's reaction after he was recently dropped and lost his place to summer signing David Raya.
Ramsdale had looked set to return for the derby on Sunday, but Raya started again and has now been preferred in each of the last three matches by Arteta.
And Ramsdale has already been linked with a move away from north London, with Chelsea and Bayern Munich reportedly keen on the England international.
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