Queens Park Rangers manager Mark Hughes has criticised referee Anthony Taylor after claiming Arsenal's winner should not have been allowed to stand.
The Hoops remain bottom of the Premier League and without a win after losing 1-0 to Mikel Arteta's late strike.
"The referee has really killed us because Arteta was clearly offside on two occasions," said Hughes.
"He has conjured up some cock-and-bull story about Ryan Nelsen being off the pitch. It has cost us the point."
The Welshman added: "I've no idea what he is going on about because Ryan Nelsen at no stage went off the field of play.
"When the referee sees it again he will realise he has made a huge mistake."
QPR had stubbornly kept out Arsenal at the Emirates before the game changed when Rangers defender Stephane Mbia was dismissed after 80 minutes.
Referee Taylor instantly produced a red card when Mbia, who was lying on the ground after being fouled and had already been awarded a free-kick, kicked out at Arsenal defender Thomas Vermaelen.
Four minutes later, Arteta prodded in the winner from close range following a goalmouth scramble.
Defeat left Rangers three points adrift of safety after nine league matches, with only three draws to their credit.
"When you are in our situation we need the officials to give the key decisions to help us and we didn't get that today," added Hughes.
"Stephane's obviously very upset. The frustration from our point was the foul had actually been given our way.
"Stephane swung out a leg. Whether or not there is any contact I'm not too sure about.
"But Vermaelen's made the most of it to ensure if the referee thought there was real contact then Stephane would be in trouble. And that was the case."