And the Gunners boss hinted he could finally bring the highly-rated 19-year-old new boy in from the cold at Leicester in the Carabao Cup tomorrow night.
Saliba was signed from St Etienne for £27m in July of last year before being sent back to the French club on loan last season.
But while many expected him to start this campaign in the Arsenal first-team, he has yet to be seen in a Gunners shirt.
Saliba is a huge prospect and was signed to much fanfare amid talk in France that he was headed for the very top of the game.
He was among the subs for Arsenal’s Community Shield win over Liverpool at Wembley at the start of the season.
But since then he has failed to make the matchday squad for the Premier League wins over Fulham and West Ham.
By contrast, new signing Gabriel Magalhaes, who linked up with Arsenal much later than Saliba but is three years older, played 90 minutes in both those games.
Now, Arteta has admitted that Saliba is still adapting to English football - and pleaded for patience with him.
Saliba missed three months of last season in France with hamstring and metatarsal injuries and is yet to settle properly in England.
But Arteta still has high hopes for him and looks set to include him against the Foxes as he bids to win the Carabao Cup.
The Arsenal boss said: “I think William is doing really well. He is adapting to the country, adapting to our club.
“We have to bear in mind that he had a really challenging season last year with the amount of injuries that he had.
Get the latest transfer news straight into your inbox!
Want to be on the ball with all of the latest football news?
Well then sign up for the brilliant new Daily Star Sport email newsletter!
From the latest transfer news to the agenda-setting stories, get it all in your email inbox.
How do you sign up?
It only takes a matter of seconds.
Simply type your email address into the box at the top of this article and hit 'subscribe'.
And that's it, job done. You'll receive an email with all of the top news stories every single morning.
You can find out more information on our email newsletter on this link here.
“But he is a player that is going to be really important in our future, things sometimes take some time and we have to respect that.”
Arteta also believes both Saliba and Gabriel will benefit from working with David Luiz at the Emirates.
He said: “I think he is a really good role model for them, for who David is as a person and as a player.
“With everything he has achieved in the game – I think they are lucky to have him around.”