Mesut Ozil has taken to social media after being dropped from the Arsenal squad for their 3-0 defeat to Manchester City on Wednesday night.
The Arsenal midfielder had been an ever-present under Arteta until this point, but was left out of the first team and wasn't even named on Arsenal's nine-man bench to take on the Premier League champions.
Initially refusing to explain why Ozil was omitted before the game, Arteta said after the match that the German playmaker was a "tactical" decision.
The Gunners lacked creativity in Ozil's absence, and were well beaten thanks to goals from Raheem Sterling, Kevin De Bruyne and Phil Foden.
David Luiz was a first half substitute for the injured Pablo Mari, but the Brazilian was at fault for the first goal, before conceding a penalty and being sent off.
On Thursday, Ozil appeared to send a cryptic message about the situation by posting an image of himself pointing to the Arsenal badge, with the caption: 'No matter what ... #M1Ö @Arsenal.'
In his post-match press conference, Arteta reiterated his decision to leave Ozil out.
"Because I need players in other positions as well and that's the reason I decided to leave him out," he told reporters.
When asked about Luiz and the defender's contract situation, Arteta replied: "I don't know what will happen with his contract.
"I know what happened today, I know the way David reacted, as a player and as a person as well he can handle the situation.
"There was a reason why I didn't select him from the start and he had to play because Pablo got injured. He's always going to try to give you his best for the condition that he's at and he's tried again. It didn't work out for him or the team but that's it."
Arsenal next travel to Brighton on Saturday, before another trip to the south coast to face Southampton.
