Mikey Harris has left his role as lead professional development phase coach to take up a similar position with Brighton.
He arrived at Fratton Park in the summer of 2014, having previously been the first team manager at Salisbury.
Harris said: “It’s been a fantastic three-and-a-half years and there have been some great moments with amazing people. I’ve loved every minute of it.
“There have been so many positive to take from my time here. Whenever a young player makes their first team debut, it’s always pretty special for any member of academy staff.
“That’s happened quite a lot over the past few years and there have been plenty of people who have put so much effort into making sure they get on to that Fratton Park pitch.
"It’s been a fantastic three-and-a-half years and there have been some great moments with amazing people."
“Seeing the likes of Conor Chaplin, Adam May, Brandon Haunstrup and Alex Bass continuing to grow has been a real pleasure.
“The FA Youth Cup is always great for the boys when they get the chance to play under the Fratton lights – pushing Manchester City all the way is a particular highlight.
“Getting to the semi-finals of the Premier League Cup last season also gave some of the boys a useful experience that would have helped their development – and we’re seeing the fruits of that now.
“It does fell weird to be leaving, but I’m looking forward to the next challenge. The opportunity to work at a Premier League club doesn’t come up often. It’s one I’m very grateful for.
“I’m very excited to leave my comfort zone, stretch myself and try to be the best coach that I can be.
"But with the good work that goes on here at Pompey, I believe that players will continue to come through.”
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