A passerby was out for a walk in Laurens, South Carolina, the night of Tuesday, August 7, when they spotted a dog chained up outside a house, lying motionless on the ground.

The dog’s skeletal frame made it hard to believe that the animal was alive — but against all odds, the dog was still breathing.

The Good Samaritan snapped a photo of the emaciated mastiff mix and reported him to animal control. Officers quickly arrived on the scene, freed the dog from his heavy leather collar and chains and rushed him to a local vet.

The 16-month-old dog, later named Champ, should have weighed 110 pounds, but had dropped to a mere 50. Though Champ seemed on the brink of death, his caretakers would soon find that he was far from giving up.

Volunteers with Rescue Dogs Rock, a New York-based rescue organization, heard of the dog’s shocking condition, and immediately knew they had to help. The next morning, the rescue contacted animal control and had Champ transferred to a nearby clinic where he could get around-the-clock medical care.

“He was in terrible shape and he needed an immediate blood transfusion,” Jackie O’Sullivan, cofounder of Rescue Dogs Rock NYC, told The Dodo. “He had no muscle mass, he couldn’t regenerate red blood cells on his own, he was anemic and his gums were white.”

“He probably wouldn’t have lived another 12 hours,” O’Sullivan added. “It was that close.”

While Champ’s future remained uncertain, his past quickly came into focus.

An investigation by the Laurens County Sheriff’s Office found that six months ago Champ was left in the care of his original owner’s ex-girlfriend, Elizabeth James, who allegedly left the dog without food or water, according to the sheriff’s report. James was arrested for animal cruelty on August 16, but has since been released on bond until her next court hearing in October, O’Sullivan noted.

The rescue shared Champ’s photo and story on Facebook, and the post quickly went viral.

“I think his story really resonated with people because there was somebody living in the home who watched this happen to him day after day,” O’Sullivan explained. “He was purposely starved while the other dogs in the home were fed. I think that people are really really angry about that.”

“She watched him deteriorate until he was almost dead,” O’Sullivan added.

Though Champ suffered unimaginable cruelty, you would never know it from his sunny personality.

“[The vet staffers] say he has an amazing disposition and is a very sweet dog,” O’Sullivan said. “He doesn’t seem to hold any grudges. He’s just happy for every little bit of attention, love and support he gets.”

After three weeks at the vet, Champ was finally deemed strong enough to continue his recovery at a medical foster home where he can feel like a real dog once again.

Since meeting his foster family for the first time on Saturday, Champ has made himself at home, rolling around in the backyard …

… and sniffing his two foster dog brothers.

While it may take up to two months for Champ to get back to a healthy weight, his fans will be with him every step of his recovery, cheering him on. Champ’s Facebook page has over 40,000 followers, and a number of his posts have reached over 100,000 people around the world. The once-helpless dog has not only sparked outrage across the internet, but become a symbol of the ultimate survivor.

“I think he’s really nothing short of miraculous,” O’Sullivan said. “When we posted that first picture people were saying, ‘Come on, get out! That dog is dead.’ And we were saying, ‘No, he’s not dead. He was very very close to the end.’”

Champ already has “a lot” of adoption applications in from all over the country, O’Sullivan noted, but when he’s ready for a forever home, the rescue will make sure his adopters will love and care for him for the rest of his life.

“We hope that he will go on to have an amazing, happy life,” O’Sullivan said. “[And] that his story will go on to help other dogs and encourage people to speak out when they see or know of abuse in their area.”