Development coach Stevie Frail has left Celtic.
Frail had overseen the Under-20s team since joining the club's backroom staff in 2009.
"I have had a great time at Celtic over the past few years and enjoyed working for a great club with some really good players," he told the club's official website.
"But I felt the time was right to move on and look at some new challenges in football."
Academy manager Tommy McIntyre will take charge of the Under-20s team on a temporary basis.