The 2002 world champion Dajka, 27, was found dead at his home in Adelaide late on Tuesday. His death is not believed to be suspicious, although it is known he had been battling depression and alcohol abuse.

Many pinpointed the cause as Dajka's expulsion from the 2004 Olympic Games for lying to the Anderson Commission when he denied injecting himself with vitamins. Neiwand, 42, dismissed those suggestions, believing both he and Dajka were products of a system that encouraged psychological wreckage but was ill-equipped to pick up the pieces.

"You would be a fool to [say] that that was the incident that led to this," Neiwand told The Herald yesterday. "It is a lot of different events that have added up. He was in the [train-on squad] with me for the 2000 Olympics. The way we were pitted against each other, he was my rival to to make the Australian team. "I used my weaponry against him, destroyed him mentally and tried to destroy him physically. That is the way the system is here in Australia. So if I look at it like that, I am part to blame for his downfall."

The brutal sport of match sprinting requires explosive strength and controlled aggression. To the winner goes the spoils.

To the loser? A four-year wait, learning to get on with life on and off the bike. It is a sport that Neiwand, a former world champion and a four-time Olympic medallist, says drove him, too, to drink and depression. He admits he also considered taking his own life.

Neiwand yesterday revealed Dajka had been planning a comeback and had even asked the Victorian to coach him for the 2012 Olympics in London.

"I got a message from him a month ago saying he is back on track and looking forward to training and going to the next Olympics," he said. "I sent a few messages back saying, 'Yeah, just get out and do some high road miles, lose some weight and we will attack the next Olympics and see what we can do'."

Neiwand would have been more like a life coach for Dajka, having travelled down the same troubled road.

Neiwand's life spiralled out of control after the 2000 Olympics. It cost him his marriage. Then in 2006 he was sentenced to prison for 18 months after breaching a court order preventing him from harassing a former girlfriend.

Neiwand was released on probation after nine months. He now works for the Sunrise Foundation that addresses depression and a Footscray bike shop owned by track coach John Beasley, who was to help Neiwand help Dajka. Neiwand has also resurrected his relationship with his former wife and his children.

When he first heard of Dajka's death on Tuesday, Neiwand said he was "dumbfounded, not wanting to believe it".

He added: "I kept ringing his number, hearing his voice and it didn't feel real. I know what he has been through, especially with depression and all that. I almost ended my life a few times. For him to go and do it, it has got to be bad.

"I spoke to Jobie about a few things - but depression in men … we don't get out there and ask for help. You only let people in on what you want to let people in on. Probably no one knew how bad he was."

Cycling Australia yesterday defended itself, saying it did have a support system for athletes who missed out on selection or who faced bans, as Dajka did in 2005 for assaulting national coach Martin Barrass.

In Dajka's case, Cycling Australia chief executive Graham Fredericks said CA paid for counselling to help him for more than a year after he was banned. "We were saying he is paying the penalty for what he did. But we also wanted to help him come back as an individual on an even footing," Fredericks said.