Mikel Arteta felt Arsenal were "very harshly done by" in a 1-0 Champions League defeat to Inter that was decided by Hakan Calhanoglu's penalty.
Inter scored the only goal of the game after Mikel Merino was punished for handling inside his own area on the stroke of half-time.
But boss Arteta felt that decision was harsh, and particularly so when Merino had earlier not been awarded a spot-kick of his own.
The Spain midfielder appeared to beat Yann Sommer to a high ball in the Inter box and took a punch to the head in the process.
That incident was cleared following a VAR check, while the decision to penalise Merino at the other end of the pitch was quickly approved.
"I am very proud of my players, the level of domination we had," Arteta told TNT Sports. "We were very harshly done by in the sense that is obvious. Both penalties.
"If you are going to give a penalty, the other one has to be because he punches him in the head.
"There is no deflection, nothing you can do in the box, so can he get away from it? If he is going to give that, the other has to be 100% a penalty."
Arteta, who reintroduced Martin Odegaard as a late substitute following injury, also sought to focus on the positives, however.
Although Inter made a number of changes to their first XI, Arteta was enthused by the manner in which Arsenal dominated their opponents, having disappointed in another 1-0 defeat at Newcastle United on Saturday.
"We should have scored a couple at least, but the way the team played, that was us at least," he added. "Every decision in the box makes a difference.
"The way we played tonight, the team can go to Chelsea and win."