Leyton Orient academy product Sam Dalby has landed a move to Leeds United, of the Championship, for an undisclosed fee.
The 18-year-old made his O’s debut aged just 16 in December 2016 to become the youngest player to appear for the club.
Dalby scored just four minutes into his League Two debut against Crawley later that month and went on to play 19 times as Orient were relegated from the Football League.
O’s director of football Martin Ling said: “I would like to wish Sam the best of luck in his future career and thank him for his efforts over his time at the Club.
“This was a good deal and opportunity for both the Club and the player, and therefore was difficult to turn down.”
Victor Orta, Leeds’ director of football, added: “We are pleased to welcome Sam to Leeds United, we believe that he can be an important player for the future.
“He has already tasted League Two and National League football, he is tall and strong, and we are confident that in a couple of years’ time he can be competing for a place in our first team.
“In the immediate future Sam will join in with our under-23s, who will help to develop him into the player we believe he can be”.