PASCO COUNTY, Fla. (CBS Local) — A Labrador Retriever is recovering nicely after undergoing reconstructive surgery for injuries suffered when he was hit by a car and left on the side of the road.

Brennan, a yellow lab, was struck on Dec. 4 in Dade City. The driver who hit him did not stay at the scene and he was left helplessly waiting for someone to stop.

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But Brennan did not have to wait alone. His brother, a chocolate lab named Dale, stayed by his side the entire time.

“That’s extraordinary, I know that there are spotted dogs that will not leave one another, we deal with that quite often,” Mac Steinmeyer, a volunteer at Maxx and Me Rescue, told WFTS. “But in this situation the dog stayed with him because of his injury.”

The dogs’ owner picked up Dale, but surrendered Brennan to Pasco County Animal Services.

Brennan’s knee, hip and ankle were left completely limp from the accident.

“Every tendon, every ligament was ripped so his patella is just floating in there and it’s got to be pretty painful,” Steinmeyer said.

The injuries were so extensive, one vet said should be put down.

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But volunteers at Maxx and Me Rescue decided to help. They took him to a specialist who determined Brennan could be saved.

Brennan underwent surgery Wednesday to rebuild all the soft tissue and ligaments in his knee.

“Today confirmed what we knew to be true: Brennan is a fighter!” the Maxx & Me Pet Rescue Facebook page declared after the procedure.

“It was a knee to remember,” Dr. Callum Hay of Veterinary Surgical Specialists is quoted as saying on Maxx & Me Pet Rescue’s Facebook page. “It’s not often you see a knee this completely ruined.”

Brennan is now on his road to recovery. He will begin rehab after three weeks of “very light activity and lots of rest.”

The process isn’t cheap, but “Maxx and Me will raise money, we will give veterinarian care as it is needed and we will do so every time we can,” said Steinmeyer.

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If you’d like to donate to Brennan’s care, click here.