Troubled swimming champion Grant Hackett has lashed out at his brother, claiming the "angry man" "beat the shit out of" him.
The Olympian was arrested on the Gold Coast on Wednesday afternoon after a disturbance at his parents' Mermaid Waters home but was released without charge.
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Hackett claims he was bashed
Grant Hackett alleges his brother bashed him while posting a photo on Instagram.
Hackett's father, Neville, called police about noon after he allegedly became agitated and verbally aggressive.
Brother Craig spoke to reporters outside the home, saying the family didn't know how to deal with his erratic behaviour.
"The whole family have done everything that we can but now it's kind of out of our hands, it really is," Craig said outside their home.
The Olympic swimming great appeared to take issue with the comments on Thursday morning, posting an image to Instagram.
"My brother comments to the media ... but does anyone know he beat the shit out of me," he said.
"Everyone knows he is an angry man."
![Grant Hackett posted an image of himself to social media on Thursday, his face bloody and bruised.](/web/20170218170124im_/http://www.theage.com.au/content/dam/images/g/u/e/1/d/f/image.related.articleLeadwide.620x349.gue1rg.png/1487238827507.jpg)
The post did not specify when the image was taken.
Hackett was reportedly being treated in hospital overnight after his doctor picked him up from the Southport watchhouse.
He told reporters after his release he was not feeling great and would be seeking help.
Following the release, his brother told the media Hackett was not his usual self.
"This is not Grant Hackett. This is a completely different person. I don't know this person, my mum and dad don't know this person," he said.
"He's there in body but he's not there in mind, soul or spirit.
"From a mental health perspective I hope something can be done."
Footage from earlier in the afternoon showed the swimmer being driven in a police car into the watchhouse, at first covering his face but later showing his handcuffs to the television cameras.
The three-time Olympic gold medallist has struggled with addiction and other personal issues since his retirement after the 2008 Beijing Games.
- with Phil Lutton and AAP