The Gunners drew 2-2 with Tottenham at the Emirates, with the former Chelsea star gifting Heung-Son Min an equaliser.
Cristian Romero put through his own net to give Mikel Arteta's troops the lead, with Son then levelling for Spurs before half-time.
Bukayo Saka scored from the penalty spot in the second half, before Jorginho's mistake allowed Son to fire home, as the points were shared.
Prior to the match, the Italy international had uploaded a post on Instagram stories showing Saka on the floor attempting to take the ball off him.
The caption read: "Don't try and press papai".
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Instead, it was Jorginho who was pressed, having dwelled on the ball in the middle of the park.
James Maddison then picked his pocket, before teeing up Son to fire beyond David Raya.
One fan said: "He just posted a hint to Spurs before the game."
Another added: "Ironic he posts, then gets pressed, loses the ball, and Spurs score."
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A third wrote: "This did not age well, bro."
The 31-year-old, following his derby howler, has since taken to Instagram to apologise to Arsenal fans after his blunder.
"A painful mistake today, but seeing how everyone reacted after my mistake to support and lift me up, my team-mates, coaches, staff and you Arsenal fans," read the caption.
"It gives me even more motivation to work harder and harder, because all of you deserve the best version of myself. Thank you so much for the support Arsenal family."
Arsenal are next in action when they take on Brentford in the Carabao Cup on Wednesday night, before facing Bournemouth in the Premier League three days later.