Mikel Arteta has branded Arsenal's "painful" 2-1 defeat at Fulham as their "worst performance of the season."

Bukayo Saka opened the scoring on five minutes, but goals from Raúl Jiménez and Bobby De Cordova-Reid condemned the Gunners to a second consecutive Premier League defeat, which leaves them fourth in the table.

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Arsenal face Liverpool in the FA Cup third round next week but do not play again in the league until Jan. 20. Arteta said his side need to correct course after another disappointing display following on Thursday's loss to West Ham.

"We certainly need that reset after today, because that's going to be in our tummy for a few days," Arteta said.

"The game against West Ham feels very different, so you can move on. It's football, it can happen.

"What happened today cannot happen again, because if you do that, we will never have the chance to be where we want to be. Today could have been a beautiful day to end the year, that's for sure.

"But these are the margins, and you have to try and find the bar. We have to look at ourselves in the mirror, because today's performance is the worst we have played all season.

"Painful and a sad day, that's how I would sum it up. We had the chance to be top of the table after 20 games with the consistency that we've shown.

"We haven't managed well enough to earn the right to win the game. Three days ago we lost a game that we deserved to win; today was a very different story."

Midfielder Declan Rice insisted Arsenal needed to be more ruthless after Saka's early opening goal.

"Today when you go 1-0 up you need to take more control, have more self-belief, more desire and the mentality needs to be better. We need to demand more from each other," Rice said on Sky Sports.

"I am not saying we didn't do it, because we still tried to push for more. But ultimately Fulham have won the game and we have to look at why they won the game.

"Once we went 1-0 up, we had to push on again, go for more. In this league there is no room to mess up. There are so many good teams around you, and obviously we want to be pushing up the top end of the table. It is a tough one to take today."