Neither man was involved in Wednesday's EFL Cup third-round tie with Brentford, where an early Reiss Nelson strike sent the Gunners through to the next stage of the competition.
Saliba and Vieira initially appeared to have been rested at the Gtech Community Stadium, where Arteta unsurprisingly sent out a second-string starting XI amid his side's league and Champions League commitments.
Arsenal were already working without Declan Rice, Bukayo Saka, Leandro Trossard, Thomas Partey, Gabriel Martinelli and Jurrien Timber for the midweek London derby, and Arteta has now delivered the worrying news that both Saliba and Vieira will need once-overs in the coming hours due to unspecified problems.
«William as well had a knock, Fabio as well wasn't involved in the last game, so we have to assess them today, see how they are and adapt to the situation because that's a big number,» Arteta told his pre-match press conference.
«Let's see how everybody is today. Obviously they weren't selected for a reason and we need to assess them again today. They weren't fit enough to be in the squad.»
While Timber (knee) and Partey (groin) are long-term absentees, all of Martinelli, Rice, Saka and Trossard are pushing to return before the international break, but Arteta revealed that none of the quartet had trained with the team by the time he faced the media.
«Declan wasn't available and had to leave the London derby. He hasn't trained yet. We have another session in an hour or two so we'll have more news about him today,» Arteta added.
«Gabriel hasn't trained and we want him back,Read on sportsmole.co.uk