The father of former boxing champion Ricky Hatton was arrested for attacking his son the day before he announced his comeback, police sources said.
It is understood that Hatton, 33, had to protect himself after his dad Ray, 61, attacked him during a heated row in the car park outside his Manchester gym.
Police were called and Hatton senior was arrested and cautioned.
A spokesman for Greater Manchester Police said: "Shortly before 11.45am on Thursday, police received reports that there had been a fight involving two men outside a health and fitness club on Market Street, Hyde."
Ricky Hatton said he was "back to fight for world titles" as he announced his return to boxing.
Hatton, who would often put on weight between fights and checked into a rehabilitation centre in London in 2010 after being photographed apparently snorting cocaine, said:
He said: "It's well documented what's happened to me, my life turned to mush. I feel I've put a bit back into the game but it didn't fill the void. I got my trainer's licence and started working in the ring and that started the fires burning and I started looking after myself a bit better.
"I'm back to fight for world titles. It's more than a comeback. It's worth more than money. A lot of people have said they don't want me to tarnish the legacy but they don't know what goes on between my ears."
Boxing promoter Frank Warren Frank Warren has urged Ricky Hatton to abandon his ill-advised comeback plans, fearing the inevitable decline of his skills will render his return an anti-climax.
The 33-year-old's last outing was a savage second-round knockout by Manny Pacquiao in May 2009 and he has since overcome drug and alcohol problems.
But Warren, who split from Hatton in 2005 after guiding him to the IBF world light-welterweight title, doubts the 33-year-old has anything left to offer.
I'd prefer Ricky not to box. He's not going to get any better at the age of 33, but it's his decision. He's returned to the gym and that has given him focus and direction, but I'd rather he stay there training and not fight. I hope he's still got it, but it won't be there...it just doesn't happen like that.
He's had a lot of problems outside the ring for a long, long time and it just won't happen. I believe he's had a good career and he should reflect on that. No-one should be encouraging him to return and I just hope it doesn't wind up being a big disappointment for him.