Arsenal goalkeeper David Raya insists they didn't deserve defeat at Newcastle.
Anthony Gordon's winner was allowed to stand after three VAR check.
Raya later said: "We are all frustrated. My point of view is I saw the ball going out of play. I think it is a foul on Gabriel, he [Joelinton] pushes him on the back and the decision was it wasn't a foul. I don't think it was supposed to go that way. And in my opinion it was offside. We are very, very disappointed.
"We competed very well today away from home. A very tough place to come. The way we played deserved a bit more than a loss. A draw would have been more fair, it was very even. Everyone in the dressing room is very frustrated and obviously angry."
On what manager Mikel Arteta said to his players after the game, he added: "He only had a little bit to say, he said he was proud on how we competed but he is frustrated with the decision."