Alex Morris will carefully manage minutes and expectations when it comes to Joel Tabiner.
The 18-year-old has started the last three League Two matches, having only previously made a couple of sub appearances.
And the homegrown attacking midfielder has caught the eye with his performances, earning praise from the Crewe management staff.
But boss Morris warned that the youngster must be looked after properly as he finds his way in the senior game.
He explained: “Tabs was out on his feet at Wimbledon, that’s why we brought him off. That’s the worry with him, we can't break him!
“I've also had loads of people asking me why I brought him off last Saturday too. I’ve not wanted to bring him off, he was our best player and I would have loved him to be on for 95 minutes in both games.
“But he was pleading to come off, and we were asking him to just give us another 10 minutes.
"He's not going to last games yet. He's an 18-year-old boy still growing into his body, and we've got to make sure that we do not break him along the way."
Tabiner, who will turn 19 next month, made four sub appearances last season. He made his first senior start in the Carabao Cup at Grimsby earlier this term.