A man has had to have his toe amputated after his hungry pet Chihuahua started eating it while he slept.

Former AFL star Campbell Brown told the gruesome tale of his father-in-law Tom Johnson's ordeal with his dog Sable on SEN.

The dog was hungry enough that two years ago it ate Mr Johnson's right big toe.

"It's too good of a story not to give to the public domain," The former Hawthorn and Gold Coast star said.

"My father-in-law Tom Johnson has got diabetes so he hasn't been able to feel his feet too well for many, many years. They just got cute pet Chihuahua called 'Sable' that sleeps on the end of the bed.

"A couple of years ago he woke up and there was blood all over the bed and he didn't know what had happened. He looked down and he was missing his right big toe and it was completely gone; gnawed off.

"They called the ambulance and he went into hospital and spent about two weeks in there because they needed to amputate the big toe and the skin grafts."

But Sable was given a second chance - unfortunately, after two years, the pup's appetite returned. "He woke up Thursday morning and had no left big toe," Mr Brown said.

"We had to go through the whole process of the amputation of the toe and skin grafts. He was in quite a bit of pain.

"I think 'Sable' is not going to be put down because we don't believe in that. But he will be going off to a farm, free to a good home I think!"

Mr Brown said it was good his father-in-law didn't sleep naked, because "it could have been a real tragedy".