Arsene Wenger felt a mistake by referee Mark Clattenburg cost Arsenal dear after they slipped to a dramatic 2-1 defeat against Everton at Goodison Park.
Arsenal missed the chance to go top of the Premier League on Tuesday as they surrendered a one-goal lead against an Everton side who had Phil Jagielka sent off in the closing minutes.
Alexis Sanchez's deflected free-kick had Arsenal on course to leapfrog leaders Chelsea, only for Wenger's team to suffer their first league defeat since the opening weekend of the season.
While he had no issue with Seamus Coleman's equaliser before the break, the French manager felt the officials missed a touch off Dominic Calvert-Lewin to award the corner that led to Ashley Williams' headed winner in the 86th minute.
"Of course it was no corner. You could see it from our side that it was no corner," Wenger told the media.
"I think we have to live with the wrong decision and it doesn't explain why we do not head the ball after you know.
"I think I'm really disappointed because [Mark] Clattenburg was in a really good position to see that play and he gave the ball out [off Arsenal] and it's not the first time we've been unlucky with decisions this season.
"Overall I don't want to speak about the referee too much, it's not my problem."
Everton manager Ronald Koeman reacted to Wenger's post-match comments by claiming his opposite number had a habit of blaming defeats on officials.
'I'm not surprised at Wenger's comments, it's the third time I've beaten him at home and the third time [he has made] it about the ref," he said.