And he reckons that experience will help the England under 21 star take his game to another level.
Moyes said: "Jack's showing signs of stepping up again.
"He has been competitive, he's more mature and realising that he's not a young boy anymore.
"He's still a young player and he's still developing but to have played 100 games is great. There are signs of someone who is maturing a bit more and looking that bit more experience. I've seen indications that he has become a bit stronger in himself. He is more demanding.
"We've always looked after Jack with kid gloves but the gloves are off with him now.
"We are demanding much more of him because he isn't that young boy anymore.
"You will accept young boys making mistakes because they're young and that will happen.
"But Jack now has to perform like a senior player and be a regular first-team player which he's getting much closer to being now."