Mikel Arteta said Ethan Nwaneri's loan move to Marseille on Friday will be the making of the 18-year-old.
Nwaneri has joined the French giants until the end of the season after struggling for minutes for the Premier League and Champions League leaders.
He scored nine times last season in a breakthrough campaign, earning a new five-year deal at the Emirates.
But Nwaneri did not start once in the Premier League this season prior to his move to the south of France.
"The talented young players that we have need minutes, and Ethan wasn't getting enough minutes," said Arteta.
"There is the fear and the insecurity of getting out of a place that has been really comfortable for him.
"At the end you have to be thrown to the sharks in an incredible football atmosphere and it's going to make him so good."
Arteta said the experience of William Saliba's positive loan spell at Marseille prior to establishing himself as a key figure in the Arsenal defence and the coaching of Roberto De Zerbi played an impact in Nwaneri's next move.
"The last thing we want to do is cut his development because he's such a talent. He lives and breathes football. That's his life," added Arteta.
"Having all the options, and understanding the experience that we had in Marseille with William and the fact that Roberto is there, who is an incredible developer of young talent and the courageous way he plays, means it is going to be a great experience for Ethan."
Arsenal look to take another step towards ending their 22-year wait to win the Premier League when Manchester United visit the Emirates on Sunday.
Arteta has a welcome dilemma on who to start up front after both Gabriel Jesus and Viktor Gyokeres scored in a 3-1 Champions League win at Inter Milan on Tuesday.
Kai Havertz has missed most of the season through injury, but is also available, albeit the German international is not yet ready to start.
"We were waiting for that," said Arteta on finally having all three forwards available.
"With the amount of games that are coming up, they're all going to have opportunities and minutes, so it's great to have them back and especially to have them in good form."