Arteta's team moved five points ahead of second-place Manchester City thanks to goals scored by Mikel Merino and Bukayo Saka at the Emirates Stadium.

The Gunners extended their unbeaten streak to 18 games across all competitions with their eighth consecutive home win.

However, Arteta, already missing first-choice centre-backs Gabriel Magalhaes and William Saliba due to injuries, faced another setback when Spanish defender Mosquera was substituted just before halftime.

Even more worryingly, England midfielder Declan Rice seemed to be dealing with a calf injury when he was taken off 10 minutes before the end.

"Obviously, it’s never good news. Declan had to leave the pitch. We don’t know yet. We have to wait until tomorrow to find out what’s wrong," said Arteta, who is also without Kai Havertz and Leandro Trossard because of injuries.

"Declan can walk but he cannot play. He has played a lot of minutes, and now we played on Wednesday night and have to play again on Saturday morning."

After Arsenal endured a tough week featuring victories over Tottenham and Bayern Munich and a draw with title contenders Chelsea, Arteta had planned to rest Saka, Jurrien Timber and Eberechi Eze in the match against the Bees.

However, all three had to come on as substitutes, causing Arteta to lament Arsenal’s injury woes and criticize the Premier League fixture schedule ahead of a challenging away game against in-form Aston Villa for Saturday’s early kickoff.

"Rest is quite a positive word to use. We had to make some changes," he stated.

"It has been a very demanding week at every level. We were asked to play three days later, with one less recovery day than them.

"We can manage playing minutes, but if they could give us just a little more time to recover and help ease the players’ welfare, that would be appreciated."