Kai Havertz scored the first goal for Arsenal, but their lead was short-lived as Declan Rice was sent off in the 49th minute. Brighton took advantage of the numerical advantage, with Joao Pedro scoring the equalizer.
Arteta later said: "We started the game really well. We scored the goal, 1-0. We started the second half really good but then there is the decision that changes the game completely."
Asked about the explanation he was given on the sending off: ", like always."
The Premier League stated Rice wa sent off for delaying a restart. Arteta added: "If it (bookings) happens throughout the game in a consistent way it is fine but it didn't. It is the inconsistency."