Yarran joined the Tigers from Carlton in exchange for pick 19 after the 2015 campaign but did not play a senior match and required time away at home in Perth to deal with personal problems.

The former star defender, 26, revealed in a candid video interview that he had battled an ice addiction.

AFL chief Gillon McLachlan defended the league's illicit-drugs policy on Friday, while Balme revealed the Tigers were aware of Yarran's issues when he was delisted.

"Obviously, yes, we did know a reasonable amount about it. The really positive thing is that it seems like he is in a much better place," Balme said.

"It was a genuine challenge. I, obviously, wasn't there when Chris came to the club and he had some real problems."

Balme, who had been at Collingwood, only joined the Tigers after the season had finished. He said he had "no idea" whether Yarran, who had been traded from the Blues, had drug issues at his former club.

There is no suggestion Yarran was on ice before joining the Tigers, with the AFL Players Association declaring on Friday players, regardless, were entitled to confidentiality even if they were to be traded.

"For the players, confidentiality's a key pillar of the [AFL illicit drugs] policy," the PA's player development boss Brett Johnson said.

"Players submit themselves to this policy voluntarily, but as a collective, they want to make sure their mental health and wellbeing is looked after and are aiming to address that through the illicit drugs policy."

Balme denied the Tigers had "off-loaded" Yarran.

"He couldn't play, he couldn't train, he was unable to do it - so we came to an agreement that he was going to go home," Balme said on SEN.

Balme did not want to go into specifics, other than to add: "Of course, we were aware of it.

"He (Yarran) would have told us because he was one of the team and he would have wanted to get better and he wanted us to help him and the club worked very hard to do it but he wasn't able then to train and do the work he had to do to give himself a chance to play, in his judgment, in the end.

"We gave him every chance to try and do that. I think we have helped him enormously and I hope we are part of the fact that he is now able to say: 'Look, I am back on track and I am trying to get myself back in gear'."

Yarran said he had been introduced to the methamphetamine by a family member. His life collapsed from that point, leading to the end of his football career.

Despite dealing with notable personal obstacles, Yarran played 119 games with the Blues and was an integral figure in their rise during the Brett Ratten era before he began to fall apart in the final year of coach Mick Malthouse's tenure. This included being dropped by interim coach John Barker for being late for training.

Yarran joined the Tigers unfit and overweight and required foot surgery on the eve of the 2016 season. He would not play a senior match. While he subsequently returned early for pre-season training before the 2017 campaign, he was still overweight and far from being in the right football condition. The two parties would cut their losses soon after.

Yarran had been working with Tom Couch, the son of the late Brownlow medallist Paul Couch, who he had hired as a personal trainer. They had travelled to Thailand in September where Yarran enrolled in an intensive training camp focusing on kick boxing.

McLachlan said Yarran's ice addiction did not mean the league's illicit-drugs policy had failed, and pointed out the player could have been in rehabilitation during his time away from training.

"It's very plausible that he was being treated by his club's medical officer and the AFL medical officer because he wasn't playing," he said on 3AW.

"Part of the model is that if you actually have a problem or vulnerability that is identified through the program and you then are not able to play and you are treated.

"I am at arm's length to it. I don't know specifically if Chris was a player like that but he didn't play football for a couple of years. That's very possible that he was being treated by the right people for the whole time."

Balme said players were hair tested twice a year, allowing clubs to keep an eye on any drug issues.

In the video, produced by the Potters House Christian Fellowship Church, Yarran opened up about his troubled childhood.

"Some of the memories I'll never forget is seeing my own mum being beaten in front of me," he said.

He said when he was nine-years old, his father had been jailed for 18 years.

Yarran, who spent a month in a $1000-a-night rehabilitation clinic but failed to kick the habit, revealed he would be high on ice and awake for days.

"I went from a fit, healthy athlete to a slob. I stacked on the weight and that's when I started to miss training because I didn't want to be seen in the messed-up state I was in," he said.

"I remember sitting in my bathroom for hours smoking meth, isolating myself from everyone, and that's when my mind would take over."

He said turning to religion had changed his life.