The officials took over three minutes to decide if Smith Rowe's goal should stand.
Arteta said he had never seen a goal like it. He didn't have to address it for a long time. Emile Smith Rowe's opener for the Gunners should have stood or not.
Smith Rowe's finish in the second half of the game between Manchester United and Arsenal on Thursday was a big talking point.
David de Gea was injured after team-mate Fred stood on his heels following a corner.
The goal was eventually awarded by the video assistant referee, with widespread confusion in the ground giving way to joy and anger for Manchester United.
Before we hear what the managers, players and pundits think of it all, let's know what happened.
The incident played out.
With 13 minutes on the clock, Martin Odegaard swung in a corner that Harry Maguire headed clear, but only as far as Mohamed Elneny, who steered the ball to Smith Rowe 20 yards out.
De Gea went down on his goalline after Fred accidentally trodden on his heel, and he stayed with his back to play. He couldn't react when Smith Rowe's shot was fired.
Seven seconds elapsed from the corner kick being taken to the shot finding the net, and then the referee blew his whistle to stop the game.
Television pictures suggested that the official was facing away from goal when Smith Rowe struck the ball, as he did not spot De Gea on the floor until the moment he struck the ball.
After the ball hit the net, he blew his whistle, wagging his finger and suggesting that he had ruled out the goal.
After advice from the VAR, the goal was awarded and a definitive decision was made.
There was nothing in the laws to suggest that the goal should be ruled out since it was Fred who impeded De Gea.
We could have been here all night.
It's always difficult if you concede three goals.
Arteta told Amazon Prime that he had never seen anything like that. The referee made the decision and the VAR checked it out.
His United counterpart Michael Carrick announced his departure from Old Manchester immediately after the match and that, coupled with the fact that United won, meant he did not spend much time discussing the incident.
"We could have been here all night and I don't have to talk about it anymore," said the 40-year-old, who will be replaced in the dugout by the incoming interim manager.
When the keeper goes down, we should stop the game, Bruno said. Players make mistakes.
I don't know if it is a mistake from the referee. That can happen if it is.
The Man Utd career was finished by winning over the "perfect night"
I've never seen anything like that before.
When Rob Green was playing for England, he scored when he was injured, like De Gea.
In 2000, he evoked a similar incident in the game between West Ham andEverton when he co-commented on the game for Radio 5 Live. In that instance, the Hammers forward was able to see that the goalkeeper was down before he stopped the game.
"I don't think Smith Rowe knew," said Green. The guy who scored past me was laughing. Smith Rowe was not.
It can happen from time to time. Nobody had the chance to catch the ball like Di Canio did. The ball was in the air, everyone was looking at it, and Martin was trying to get out of the way.
Everyone in the stadium could see that De Gea was on the floor with his back to the game and his teammate stamped on his ankle. It is unfortunate.
"As an ex-goalkeeper, I am sitting here thinking 'bit of common sense, guys, you can't save the ball if you're down injured with your back to the game'."
I understand the clinical nature of refereeing and the argument that says there is nothing to stop it being a goal. In the cold light of day, you wonder what the sporting decision is. I don't think it should have been allowed.
If Green was speaking for the goalkeeper's union, Alan Shearer was on hand to give a strikers take.
He said that his immediate thought was goal. I didn't see a foul on the keeper and I didn't hear the referee blow. I believe that happens in every game. I don't think the keeper should be going down like that because he should be looking at where the ball is.
If it had been a serious injury, then there's an argument that maybe they should have let United score, but a minute later, De Gea's walking around and not limping.
Mark Clattenburg was with Shearer to offer a view from an official's point of view.
"I've never seen anything like this before," he said. Martin was powerless. He would have felt that there was a foul but he couldn't blow his whistle until the ball was in the goal.
If he blew the whistle first, there would be more controversy. I'm sure Jadon would have stopped playing if he had won the ball.
He didn't see De Gea falling. When Smith Rowe is striking the ball, Martin is not looking at the keeper, but he is wondering why De Gea is down. He will have thought there was a foul.
The incident at Elland Road in which a man was injured while playing for Elland Road in the game against Aston Villa in the middle of the year evokes memories of that.
The gesture that earned him a fair play award was the one he made when he decided to allow Villa to score an equalising goal.
Click here to vote if you are viewing the page on the app.
