Australian former tennis star Jelena Dokic revealed on Monday that she came close to taking her own life just a few weeks ago.

The 39-year-old, who rose to a career-high world ranking of four in 2002, wrote a lengthy and heartfelt message on Instagram along with a picture of herself in tears. 

Dokic, who sprang to prominence at Wimbledon in 1999 when she stunned world number one Martina Hingis in the first round, said she has been suffering with mental illness and nearly resorted to suicide on April 28.

"I almost jumped off my 26th floor balcony and took my own life. Will never forget the day," she wrote on Instagram.

"Everything is blurry. Everything is dark. No tone, no picture, nothing makes sense... just tears, sadness, depression, anxiety and pain. 

"The last six months have been tough. It's been constant crying everywhere."

"Will never forget the day, I just wanted the pain and the suffering to stop," she added.

"I pulled myself off the edge, don't even know how I managed to do it."

Dokic won six WTA singles titles during her career and reached the semi-finals of Wimbledon in 2000.

But she struggled for years to escape the influence of her volatile father Damir, tumbling down the rankings into the 600s during her well-documented split from him.

The family rift followed a series of bizarre episodes including Damir being banned from the All England Club at Wimbledon and at one point claiming his daughter had been kidnapped.

Dokic, who has worked as a television commentator since retirement, is now encouraging others struggling with their mental health to seek assistance.

"Getting professional help saved my life," she said in her Instagram message.

"I am writing this because I know I am not the only one struggling. Just know that you are not alone. 

"I am not going to say that I am doing great now but I am definitely on the road to recovery."

She concluded: "I will be back stronger than ever."