Arthur Okonkwo made his first competitive start in senior football at the weekend when his Crewe Alexandra team beat Rochdale 2-1. It came just hours after he completed his loan move to the club.
Nuno Tavares also debuted for Olympique Marseille in their 2-0 friendly loss against AC Milan.
He was a second-half substitute for former Gunner, Sead Kolasinac, the Arsenal website reports.
Auston Trusty, Tyreece John-Jules, Ryan Alebiosu, Nikolaj Moller Ovie Ejeheri and Omar Rekik also played for their loan clubs in competitive and friendly matches over the weekend.
Just Arsenal Opinion
Sending out our youngsters on loan is a very important part of their development.
These players will get the playing minutes that we cannot guarantee them at the Emirates and it will make them much better.
Mikel Arteta has shown a commitment to handing chances to graduates of the Hale End academy.
This will serve as an extra motivation to the loanees to be in their best form because they are being watched by their manager and will get chances if they do well.
The opposite is also the case. If they do badly, they will be forgotten.
Meanwhile, fans will hope this is a good season for their club and it ends in a top-four finish.