The former Brentford man caused a stir when he went down in last weekend's 2-2 draw with Manchester City, with many believing that he was simply trying to buy Arsenal a bit of time at the Etihad.
However, Raya was then seen limping past reporters in the mixed zone, suggesting that his injury was genuine, and he was missing from the squad for the midweek 5-1 win over Bolton Wanderers in the EFL Cup.
Raya's injury, Neto's ineligibility and Tommy Setford's own issue left Arteta no choice but to start 16-year-old Jack Porter in the cup, and the Gunners boss offered a curt update when asked Raya could be back for the visit of the Foxes.
It appears that the North London giants will have to make do without their first-choice goalkeeper for another week, though, as Arsenal writer Connor Humm reports that he was not seen arriving with the rest of the team.
Neto set to make Arsenal debut in Leicester showdown?
As a result, Bournemouth loanee Neto is likely to come in for his first Arsenal appearance when the Gunners host Steve Cooper's side, having been forced to miss the Bolton clash on account of being cup-tied.
The experienced Brazilian was given a public vote of confidence by Arteta in Friday's pre-game press conference, where the Spaniard suggested that he could 'throw in' Neto for his Arsenal baptism on Saturday.
Asked why he targeted Neto specifically, Arteta said: "We had to react very quickly with the departure of Aaron [Ramsdale], and we had him on our list for a few years already.
"He's played in various countries at the highest level in different roles and has always fulfilled it in the right way. I believe he was the right player [to bring in] because he was in the Premier League, he had the experience, and he's someone we can throw in at any moment."
While Raya will presumably be unavailable for Arsenal this weekend, Humm had more positive news to share on Ben White, who was reportedly seen with the rest of the squad at the hotel.
The England international was also absent from the squad for the Bolton hammering after playing just 45 minutes of the draw with Man City, where he started on the bench due to a fitness problem.
Arteta did not initially plan on giving White any minutes at the Etihad, but his hand was forced by Leandro Trossard's sending off, which led him to sacrifice Bukayo Saka for an extra defender.
Which other Arsenal players are missing for Leicester clash?
Raya would be one of six guaranteed Arsenal absentees for tomorrow should he indeed be unavailable, as Martin Odegaard (ankle), Mikel Merino (shoulder), Takehiro Tomiyasu (knee), Kieran Tierney (hamstring) and Oleksandr Zinchenko (calf) are all sidelined.
However, Arteta confirmed on Friday that Tomiyasu and Merino were both back in partial training, and the latter could even make his belated debut for the Gunners in next weekend's showdown with Southampton.
On another bright note - or two - Jurrien Timber and Myles Lewis-Skelly are also expected to be fine for the visit of Leicester despite suffering knocks against Man City and Bolton respectively.