Arteta's side moved five points clear of second-placed Manchester City thanks to goals from Mikel Merino and Bukayo Saka at the Emirates Stadium.

The Gunners extended their unbeaten run to 18 matches in all competitions with an eighth successive home victory.

But Arteta, already without first-choice centre-backs Gabriel Magalhaes and William Saliba through injury, was dealt a blow when Spanish defender Mosquera was forced off just before half-time.

Even more alarmingly, England midfielder Declan Rice appeared to be nursing a calf injury when he was substituted 10 minutes from full-time.

"Obviously it's never good news. Declan had to come off. We don't know. We have to see tomorrow what he's got," said Arteta, who is also without Kai Havertz and Leandro Trossard due to injuries.

"Declan can walk. He cannot play. The thing is, he's played a lot of minutes but as well, now we played Wednesday night and we have to play Saturday morning as well."

With Arsenal having battled through a gruelling week featuring wins over Tottenham and Bayern Munich and a draw with title rivals Chelsea, Arteta had taken the opportunity to give a rest to Saka, Jurrien Timber and Eberechi Eze against the Bees.

But all three were eventually needed off the bench, leaving Arteta to bemoan Arsenal's injury curse and question the Premier League fixture schedule ahead of a testing trip to in-form Aston Villa for Saturday's early kick-off.

"Rest, that's quite a positive word to use. We had to make some changes," he said.

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

"We can play minutes but if they can please give us just a little more time to recover and to make the welfare of these players a little bit easier, that would be great."

Declan Rice

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