The dog - that Caswell County shelter employees have named Mason - was covered in scars.
They say those markings are usually found on bait dogs - used for fight training.
"I don't know how he got away from that situation, but he is very lucky to be with us. Unfortunately, there is a lot of other dogs that are not, " said Mason's foster owner Galyna Kapernski.
After a thorough check, a Caswell County vet said it was immediately clear that Mason had been used for fighting.
"Leg wounds, arm wounds, head wounds...he had been this way a long time. For a dog to look like that, to me, means he has been a bait dog, " said the shelter manager, describing a weaker dog that strong dogs attack in fight training.
For now, Kapernski's family is providing Mason a foster home - where he plays happily with other dogs and children, despite what he has been through."He is just so sweet. He comes and he wiggles his tail. He is very friendly, " Karpenski said. In 2007, police busted a dog fighting ring in Caswell County in which several dogs had to be put down. Unlike Mason, they could not be rehabilitated.
Rings have also popped up in Danville over the years, but many times they don't go to trial.
"What people sometimes don't understand is, it is hard to prove, " said Danville Area Humane Society Executive Director Paulette Dean.
Signs to watch out for include large groups of pit bulls in one area, dogs with multiple scars, and backyard conditioning equipment - like treadmills and spring poles.
"Every time we see an animal that's been hurt or that's been abused we think, this one now is safe, but there are more out there, "