Saliba and Sokratis Papastathopoulos were not registered for the competition, and with Rob Holding, Calum Chambers, Pablo Mari and David Luiz all injured, Arteta is left with Shkodran Mustafi and Gabriel Magalhaes as his only centre backs for Thursday’s match against Irish side Dundalk.

“I feel really bad for William Saliba,” Arteta told reporters. “Because we had so many central defenders, we decided to leave him out of the squad, which was really hurtful for me to do.”

Saliba, who spent last season on loan at St Etienne, has yet to make his Arsenal debut but Arteta said the French teenager is making steady progress in training.

“He’s feeling a lot more confident around the place, his language is improving and he’s starting to understand much better what we’re doing physically,” he added.