The 30-year old has been advised that two bulging discs in his neck present a high risk of serious injury if he continues to play contact sport, so he has decided to call fulltime on his 12 year professional playing career.
"I've been told the injury will heal itself over time providing I don’t receive a serious knock to that part of my body. The only way to ensure that doesn’t happen is to stop playing football altogether," McLinden said today, after breaking the news to his Reds team-mates.
"I've been fortunate to have had a long and - in my opinion - successful career in rugby league and rugby union here in Australia and overseas; I've made a lot of friends and enjoyed myself immensely. But I'm realistic enough to know you can't play forever and I retire with no regrets.
"It's time now to move on to a new stage of my life and to do some of the things I've had in the back of my mind that I wanted to do, but haven't had the time because of football."
Away from rugby McLinden has a diverse range of interests, having studied courses in fitness, business and journalism. He's also produced short films and has a strong interest in media.
"With the support of the Reds player development program I gained my personal training certificate so that's something I might start off with. But I have a few ideas I'd like to pursue."
McLinden joined the Reds for the 2009 season on a two year contract after a decorated seven year career in rugby league with the Canberra Raiders, followed by four seasons playing league in the UK.
He made an impressively fast transition to rugby and made his starting debut for the Reds at fullback after only a handful of trial matches and a maiden appearance off the bench in the opening round of 2009 against the formidable Bulls.
He went on to play in all but one of the Reds' 13 Super Rugby games in 2009, scoring three tries.
QR Reds Head Coach Ewen McKenzie said the news had come as a shock to the team and to McLinden, who had impressed the new coaching staff both on and off the field.
"We certainly viewed Mark as an integral member of the team and valued his leadership qualities and work ethic. In my short period with the team he impressed me with his approach to training and his all round professionalism," McKenzie said.
"However having been through the same type of injury myself I know he's made completely the right decision.
"While this has come completely out of the blue, we do have some fullback options in the squad and the Academy and we'll be examining those first before deciding whether to look further afield.
"In the meantime, our main focus now will be on helping Mark make this adjustment in his life and giving him whatever support he needs in that."