Adelaide star Eddie Betts has posted an emotional message of support for former teammate Chris Yarran, who has walked away from his contract with Richmond to focus on his battle with mental health issues.

Yarran effectively retired on Tuesday, forgoing the final two years of his contract to return home to Western Australia and be closer to family support.

It is understood Yarran has not ruled out playing at some level next season, and under the terms of his release he would be eligible to play in the WAFL.  

Betts, who played alongside Yarran for five seasons at Carlton between 2009 and 2013, said it was hard to see his former sidekick leaving the elite level in tough circumstances.   

"It is so hard to see you finish like this but you'll always be the biggest gun in my eyes," Betts wrote on social media. 

"I have missed playing beside you but I'll always be here for you.

"To all my brothers in AFL, I know it can get tough at times but we just have to speak up and help each other out … it's hard seeing young indigenous players pack up and leave.

"Mental health doesn't discriminate."

Betts also called on fans to "keep your commentary on this topic appropriate".

"You never know what people are suffering from," he said. "These types of situations need support and understanding, not jokes or ridicule."

Yarran played 119 games for the Blues and crossed to the Tigers in the final half-hour of the 2015 NAB AFL Trade Period.