The key forward was taken by Brisbane with pick number nine in the 2005 National Draft and played 82 games for the Lions before a big-money trade to Melbourne at the end of the 2011 season.

But his time with the Demons was blighted by a chronic foot injury, and he managed just 15 games.

A club statement said Clark had been dealing with mental illness for the past 12 months and had been diagnosed with clinical depression.

“I just want to say thank you to the Melbourne Football Club, firstly for giving me the chance to play for them and secondly for taking care of me during my time there,” Clark said.

“Everyone at the club has been so supportive of me during some very challenging times, which I will always be appreciative of.

Everyone at the club has been so supportive of me during some very challenging times

“Finally I want to say thank you to the players and members for being there for me. I’m sorry I wasn’t out on the field more, but with my injuries, it just wasn’t to be.

“I am very grateful for everything Melbourne has done for me.  I will always consider myself a Melbourne player and a Melbourne person.”

Melbourne’s football manager Josh Mahoney said the club fully supported Clark’s move.

“Mitch’s health has been the priority in this situation and after assessing all potential options, Mitch decided it was best for him to retire from AFL football,” Mahoney said.

“The Melbourne Football Club supports this decision.

“The club has been supporting Mitch throughout his illness, providing the best resources to assist him in his rehabilitation. We will continue to support him throughout the next phase of his life.”

For help or information on depression and suicide:   

• Lifeline: 13 11 14
• Suicide Call Back Service: 1300 659 467
• MensLine Australia: 1300 78 99 78
• Beyondblue support service: 1300 22 4636
• Lifeline: 13 11 14
• SANE Australia Helpline 1800 18 SANE (7263)