Arsenal manager Mikel Arteta described as "unacceptable" the way his side conceded two late goals to lose 2-1 at Brighton and Hove Albion on Saturday, their second defeat since the restart of the Premier League.
Nicolas Pepe's delightful free kick looked like giving Arsenal the points but Lewis Dunk equalised for the hosts before Neal Maupay struck five minutes into stoppage time.
Defeat left Arsenal in ninth spot in the table with 40 points from 30 games, six behind fifth-placed Manchester United.
"I am very frustrated," Arteta said.
"It is unacceptable the way we lost the game. We like competing and I know we have a young squad but still, we threw the game away. We had to put it to bed earlier.
Before the Premier League was suspended because of the pandemic, Arsenal were on a three-game winning run in the league that had revived their hopes of qualifying for Europe.
However, after losing to Manchester City on Wednesday and now Brighton, it looks a tough task.
"We need to try to lift the players. There's a lot of things that they've done really well, but we don't compete," Arteta said. "At this level you can't give the goals that we give away.
"It's impossible. I know that we are a very, very young team but in the Premier League if you make two mistakes like this, you lost two goals. We can't accept that."
Arsenal also lost keeper Bernd Leno to a knee injury after he tangled with Maupay just before halftime. Arsenal's players reacted angrily at the French forward who hit back at suggestions he was reckless.
"Some of their players need to learn what is humilty — especially one of them. He was talking all game, he was saying bad things," Maupay said. "I don't want to say because I could be in trouble. I just said that this is what happens when you talk too much on the pitch.
"I just went for the ball. I am that type of player — I don't want to stop until the referee blows the whistle."
Arteta stopped short of criticising him.
"I always believe players never have the intention to hurt anybody and I'm sure he didn't have the intention to do that."
It was a massive three points for Brighton who gave themselves a five-point cushion over third-from-bottom Bournemouth in the relegation battle.