Audley Harrison has retired from boxing for a second time after revealing he is suffering the effects of head injuries.
The 2000 Olympic super-heavyweight champion says he now suffers from vision and balance problems, moodiness and irritability.
His decision was prompted by research into concussion and brain injuries, and after seeing medical specialists.
"After years of denial and sticking to my guns, I'm finally getting out of my own way," said Harrison, 43.
"I've suffered a few traumatic brain injuries (TBIs) and will have to work hard to reverse some of the effects taking punches to the head has brought about to my overall health.
"I have vision problems, vestibular injuries that lead to balance disturbances, and have bouts of serious irritability and moodiness that come with TBI recovery."
|Audley Harrison in numbers|
|Height: 1.97m||Wins: 31|
|Reach: 218cm||Wins by KO: 23|
|Turned pro: 2001||Losses: 7|
|Professional fights: 38||Gold medals: 2 (Sydney Olympics 2000 and Kuala Lumpur Commonwealth Games 1998)|
Harrison also revealed he is now "likely to file for bankruptcy".
Harrison, who suffered seven defeats in his 38 professional fights, first quit the sport in April 2013 after losing to American Deontay Wilder in 70 seconds, only to make a U-turn shortly after. But he has not fought since.
The Londoner had challenged for the world title against fellow Briton David Haye in 2010 but lost in the third round.
And his career looked to be over in October 2012 when he was knocked out in the first round by another Briton, David Price.
But he won a Prizefighter tournament the following year to briefly revive his hopes of one day winning a heavyweight world title.