William Saliba has "enormous potential" and he "will succeed" at Arsenal, according to his ex-Saint-Etienne team-mate Harold Moukoudi.
Arsenal invested £27 million ($35m) in Saliba's talent in July 2019, before allowing him to remain at Saint-Etienne on loan for the duration of the 2019-20 campaign.
The 19-year-old joined up with his new team-mates at Emirates Stadium over the summer but is still waiting for his chance to shine at senior level for the Gunners.
The Frenchman hasn't seen a single minute of Premier League, EFL Cup or Europa League action at the start of the season, and has had to be content with just two outings for Arsenal U23s to date.
Saliba was touted for another loan move before the domestic transfer deadline, with Watford and Norwich reportedly leading a long line of potential suitors in the Championship.
Saint-Etienne also tried to bring back the defender on a temporary basis prior to the closure of the European market on October 5, but a final deal never came to fruition.
The Ligue 1 outfit expressed their frustration via an official statement on their website, which read: "Long before the transfer window closed, AS Saint-Etienne had reached an agreement with William Saliba and accepted Arsenal's offer for a one-season loan.
“Unfortunately, all the administrative conditions could not be met in time, in England, for the completion of the deal.
“The disappointment is great for ASSE and William Saliba, who was particularly determined to return to a club where he has flourished.”
Saliba now has no choice but to bide his time and fight for a place in Arteta's squad, with Moukoudi confident he will make the grade at Emirates Stadium if he continues to put in the necessary hard work behind the scenes.
"I told him not to worry and to keep working. It will pay off," the Arsenal centre-back's old colleague told ButFootballClub. "With the qualities he has, I am sure he will bounce back. He has enormous potential, no one can deny that.
"He has to hang on, take his situation patiently, but he will succeed. It's certain."
Saliba will be back in contention for minutes when the Gunners play host to Leicester City in the Premier League on Sunday night.