The youngster was a second-half subtitute in Arsenal's 2-2 draw at Manchester City.
Ali told Arsenal's website: “They have to train well with the first team and get buy-in from the first team players.
“They’ve got to impress Mikel and they’ve done that. I’m really proud of those boys because every day they turn up they’ve got an elite mindset. To represent Arsenal is an unbelievable honour. We’re so thankful for our first team, who don’t gift opportunities easily, and it should be like that.
"They’ve got to earn it and deserve it so it’s even sweeter when they do get on the pitch. I’m gutted that we conceded so late but I’m so proud of Myles, Ethan and all of the boys who have been in and around the first team, as well as all of these boys because we support them really well.
“We’ve got a really strong relationship and we try to align things as much as possible and I think that is really beneficial for Arsenal as a football club and everything we try to strive for.”