The Gunners have just two centre-backs available for Thursday’s Europa League game against Dundalk as Calum Chambers, David Luiz, Pablo Mari and Rob Holding are all not fit to feature.
Arsenal are also unable to field both Sokratis Papastathopoulos and Saliba as they were not registered for the Europa League squad.
Arteta appeared to hint on Wednesday he was disappointed not to be able to play Saliba, who was left out of the squad as Arsenal already had 19 non-homegrown players – which is two more than Uefa allow.
The French teenager, who almost went on loan in the summer, has struggled to adapt to life in England and he is still yet to make his Arsenal debut, but Arteta has revealed he is now progressing well.
“He’s in a much better place,” he said. “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’s played a few games, with the Under-23s, which he needed because he didn’t play any football in the last seven or eight months. Things are progressively getting better and better.
“I feel really bad for William Saliba. Because we had so many central defenders we decided to leave him out of the [Europa League] squad, which was really hurtful for me to do.
“I was hoping that Pablo [Mari] would be back in two weeks, but he had a setback and then we don’t have Pablo and we don't have William when he’s fit and available to play. But when you make those decisions you can’t always think about every possible outcome.”
Arsenal’s run of injuries at centre-back is certainly bad luck, particularly given how congested the fixture schedule is this season, but Arteta is not complaining.
“I feel really lucky to be where I am sitting right now,” he said. “But this can happen. If we had ten [centre-backs] maybe we would still be in the same position.
“There are different cases. Musti (Shkodran Mustafi) was carrying that injury from last season, with Calum [Chambers] it’s exactly the same situation.
“With Pablo [Mari] he had surgery on his ankle and David [Luiz] rarely gets injured and we don’t think it’s a big thing, but it’s going to keep him out for a few weeks.
“And Rob [Holding] is the same case, but if anything with him it’s the amount of minutes he has already played when in the last nine or 12 months he hadn’t played but he had to step in because we didn’t have many solutions there. So it’s a combination of factors.
"We have to cautious and we have to manage that position very carefully because if we lose another one, then we will be in big trouble, so of course, we will have to keep an eye on how we manage the squad in the next two or three games."