Derby County boss Nigel Clough praised record-breaking schoolboy Mason Bennett for his maturity after handing the striker his debut at Middlesbrough.
Bennett, just 15 years and 99 days old, became the club's youngest player when he started in the 2-0 defeat.
Clough said: "It was a very mature debut but he'll be back with the under-18s next week because it is half-term."
In order to play at the Riverside, Bennett needed permission from his mother and his school.
The England Under-16 international would also have taken the record for youngest scorer in Football League had he succeeded with a second-half chance that rattled the bar, or a first-half header that went wide.
That record is currently held by Ronnie Dix of Bristol Rovers, who scored aged 15 and 180 days in 1928.
Bennett, who beat the Rams appearance record previously set by Lee Holmes, was unable to make his debut against Reading in midweek because he had school the next day.
"He's not bad for a kid of 15 years and 99 days is he?" added Clough. "He got a little tired towards the end and gave the ball away a few times but to play at this level like that was very impressive.
"He wasn't far away from a goal in the second half when he put it against the bar. He'll be thinking about that one for a while.
"He didn't find out he was playing until 2pm so he didn't have too much time to get nervous. He's done very well but we can't expect that in every game and he won't be involved every week. That's too much to expect."