The administrator, who also worked for the Manchester FA alongside his duties at Hurst Cross, sung the club's praises on Friday after being unveiled as the new football secretary for League One Oldham Athletic.
Cooper, pictured, was also hailed by his colleagues at the Robins in a statement announcing his departure for Boundary Park and inviting applications from possible successors with the start of the 2017-18 season less than three weeks away.
The club said: "Our very own match day secretary Richard Cooper has deservedly landed a top job as football secretary for Oldham Athletic. Unfortunately, this means that Richard will be leaving Hurst Cross where he has been our matchday secretary on a voluntary basis since January 2016. Richard always went the extra mile at Hurst Cross and his work ethic and personality will be missed."
New Latics man Cooper said: "It has been a lifelong dream to work within football but specifically professional football. The reason I joined Ashton United was to get experience within a football club for future employability. However although I got this I also became part of a family.
"I had a few different options when I came to Hurst Cross but it was the welcome and the people that made me choose this club. I have had a great experience, maybe a little shorter than I expected but I have had a great offer I could not turn down.
"I would like to place on record my thanks to everyone at Ashton United. [Club secretary] Andy Finnigan has been amazing and allowed me to take on a lot of the secretarial work. My experience is down to what Andy has empowered me to do. [Vice-chairman] Steve Hobson has been very supportive of everything I have done and was the one responsible for talking me into coming to Ashton initially."
He added: "Finally, the managers and players I have worked with, Phillo and Ackers then Jody and Will, they have been brilliant with me. I am really excited to be joining a great club like Oldham Athletic but I will miss Ashton. I will look out for the results every week and I will be back at the Cross when I can. Once a Robin always a Robin!"
Vice-chairman Steve Hobson said: "Whilst Ashton United is sorry to see Richard move on we are not surprised at his success. We are delighted that we have been able to help him climb yet another rung on the ladder to success, and will watch his future career path with interest.
"Richard is yet another club volunteer who has used his time at Hurst Cross to move to bigger and better things, hot on the heels of club media manager Mikey Brown, who recently supported the England U20s at the Toulon Tournament in France."
He added: "Richard will always be welcome at Hurst Cross and he may even come back to the club at some capacity in his lifetime. Thank you and good luck from everyone at Ashton United Richard."
For more information on the vacant matchday secretary role contact club secretary Andy Finnigan.
Images courtesy of Ashton United
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