The father of a 5-year-old Brooklyn boy who was mauled by a pit bull while trying to save his younger siblings wept Sunday as he recalled seeing the horrendous injuries to his son’s face.

“I said, ‘You’re beautiful.You’re a champ. Daddy is real proud of you. You did a great job,’ ” Joel Rivera told The Post, sobbing outside Cohen Children’s Medical Center in Glen Oaks, Queens, where the boy, Jeremiah, was in critical but stable condition with about 2,000 stitches.

Rivera recalled finding Jeremiah on the living-room floor at their East New York home, choking on his own blood,

“He didn’t have a face,” the father said. “Just teeth, that was all I could see.”

“He wasn’t breathing. I yelled at him and said, ‘Come back! I love you! Come back! I got you! Come back to Daddy!’

“He made a noise, and [he] started breathing,” the father said.

Rivera had been caring for the dog and another pit bull for a neighbor whose home had been destroyed by a fire, a relative said.

“He was doing this guy a favor that could have cost his son his life and did cost him his face,” Jeremiah’s uncle, Moe Bastic, told The Post.

The dogs were kept in wire cages in the home, but one escaped Friday evening after Rivera had made grilled-cheese sandwiches for his kids and dozed off on the couch as they watched cartoons.

Rivera and another uncle, Michael Pride, said Jeremiah was protecting his brother and sister, ages 3 and 1, when he was mauled. It was the 1-year-old girl’s birthday.

The dad said that after he woke up to find his son maimed, he ran into the street and flagged down a firetruck, then fainted on the stoop as the firefighters rushed in to save his son.

When he regained consciousness, cops had swarmed the building and his child was en route to the hospital.

“I begged them to shoot the damn dog. I was screaming, ‘Shoot the damn dog!’ ” Rivera recalled. “I asked them to give me the gun so I could shoot the dog. They put the dog in the bathroom. Then someone took [the dogs].

“Then at the hospital, they let me see [Jeremiah],” Rivera said.

He said he whispered to his ailing boy, “I’m here. I got you.”

Jeremiah suffered deep lacerations on his face and neck and lost two pints of blood, his dad said.

He said he thinks there are some 2,000 stitches in the boy’s face.

Jeremiah’s mother, Latoya White, was by their son’s side all day Sunday, never leaving the hospital room.

At one point, Rivera broke down in sobs looking at his own bloodstained clothing.

“This is [Jeremiah’s] blood on my shoes and my pants,” he said. “The last time I had his blood on me was when I cut his umbilical cord. I am responsible for this. This is my fault. Man’s best friend? How you going to do this to my son and be called man’s best friend?”

Both pit bulls were seized by the city’s Animal Care and Control and are under observation. Their fate remains uncertain.

Bastic has started a GoFundMe page to raise money for Jeremiah’s facial reconstruction. As of Sunday afternoon, the page had raised $430 out of a $100,000 goal.