Brown tried to talk him out of joining then League One Bournemouth four years ago.
“We really tried to keep him but when a boy sees an opportunity and wants to take it there's not a lot you can do.
“We couldn't hold him back because it was a move he was desperate to make.
“I just thought it was too soon but, looking back now, I was wrong.
“Ryan went down there, got more money and has won two promotions and is now playing in the English Premier League."