Beijing diving gold medallist Matthew Mitcham ahead of his return to major competition.

Matthew Mitcham: "I felt so much shame that I wasn’t able to reach out to anybody." Photo: Tamara Dean

For diver Matthew Mitcham, it has been a slow climb back up to the 10-metre platform.

The 25-year-old Olympic gold medallist - who crashed out at the London Olympic Games last year - is back for the Australian Open Championships at Sydney Olympic Park this weekend.

He will compete in four springboard and platform events.

Back in the water: Matthew Mitcham ahead of his return to major competition.

Back in the water: Matthew Mitcham ahead of his return to major competition. Photo: Tamara Dean

But after battling serious injury - and drug addiction - he has been "baby stepping" his way up the tower.

Last year, Mitcham revealed he spent 2011 fighting a methamphetamine addiction after struggling for years with depression, anxiety and panic attacks.

"I felt so much shame that I wasn't able to reach out to anybody," he says. "I suffered unnecessarily for a really long time."

Matthew Mitcham: "I felt so much shame that I wasn’t able to reach out to anybody."

"A reward for sobriety is being able to talk to people about it": Matthew Mitcham. Photo: Tamara Dean

Mitcham admits that conquering crystal meth was only possible because of the support of his inner circle, attending regular Narcotics Anonymous meetings and educating others about drug dependence.

"A reward for sobriety is being able to talk to people about it. I remember how much pain I was in when I was in active addiction. I want to break down the stigma around addiction and depression - not just in the wider community but in sport as well."

He does regular youth work and early next year will perform a series of cabaret shows based on his autobiography, Twists and Turns.

"I can handle things life throws at me that I might not have before," he says.

After some speculation he would retire after London, Mitcham says he never stopped training, instead turning to the three-metre springboard to propel him back into the sport.

He also spent time working on his "plan Bs" - a university science degree, personal training course and cabaret.

This weekend, Mitcham will compete in the 10-metre platform, the three and one-metre springboard and the three-metre synchronised event.

He has scaled up the technical difficulty of his dives since London when a recurring abdominal tear forced him to pull back.

He will be joined at the Australian Open Championships by 21-year-old Beijing Games silver medallist Melissa Wu, who, like Mitcham, has been plagued by back injury.

"I'm pretty happy with my preparation going into this competition," says Wu, who has spent a year recovering from a disc bulge.

Wu's goal is to compete in the Rio Olympics in 2016, but Mitcham is more cautious.

"My planning at the moment only goes as far as the Commonwealth Games in Glasgow next year.

I've got an Olympic gold medal and a World Cup gold medal," he says.

"The only big one I'm missing is a Commonwealth gold. That would complete my trifecta and would make me a very happy man."