A rottweiler puppy who was considered undesirable because he had a limp has amazed the internet with his remarkable transformation—all because his owners took a chance on him.

Leah Alisse, 29, of Temecula, California, has melted hearts online after sharing a video on TikTok (@leahalisse) showing how far her rottweiler pup, Gunther, has come in the last two years. Early footage shows Gunther struggling to walk on his hind leg and limping before he got help, then reveals the incredible transformation he's had over time.

When she first saw him at 10 weeks old, he was the only puppy left at the breeder as "no one wanted him" because of his limp. Alisse told Newsweek that she was "scared he would be put down" if she didn't take him home, so she took the leap and gave Gunther a loving place to live.

She knew it was the best decision, but she was nervous as she watched her new puppy struggling to move around. As it turns out, all he needed was someone to give him a chance and a little bit of support, because before long, the limp was completely gone.

"From what we were told, the original people who purchased him didn't want him because of the injury, and no one else wanted to take a chance on him," Alisse said.

"It was really shocking and heartbreaking to see because it looked so painful. His leg had no stability at the ankle joint and was just bending on itself. The breeder said the limp appeared when he was a few weeks old, but his X-rays showed no breaks and didn't offer any solutions."

At first, Alisse found it hard to watch Gunther move with such difficulty, but she says she was "determined to give him the best life" she possibly could. She started researching for answers and spoke to a vet who believes it might have been nerve damage after being sat on by his mom or being dropped.

It just so happened that, at the time, Alisse's father-in-law was doing physical therapy for a foot drop—a condition that causes difficulty lifting the front part of the foot and causes it to drag on the ground, according to the Mayo Clinic.

Alisse had the idea to try out some of his exercises and stretches on Gunther's leg, and within three days, the rottweiler was already showing signs of improvement.

"He was such a calm and well-behaved pup, so he would just lay on our laps and let us do the exercises throughout the day. We then put him in the pool and did our best to keep our hands under his foot to create some resistance and get those muscles activated. We continued to keep up with both the pool once a day and the movement exercises," Alisse continued.

"Within days, he already had stability on his leg and was running around trying to play with our other dogs, a husky and a rottweiler. His leg would still give out, but it was such a huge improvement in a short amount of time. Within two weeks his leg was hardly giving out anymore."

Now at 2 years old, Gunther is just like every other dog and loves running around. There is still some laxity in his ankle, but he doesn't limp anymore, and the joint doesn't bend outward. Alisse continues with the exercises and spends time in the pool with him, and she's hopeful that over time they can reduce the problem even more.

After sharing Gunther's incredible recovery on TikTok, the video went viral, with more than 450,400 views and over 18,800 likes in just a matter of days. The adorable clip melted plenty of hearts online, as many social media users praised Alisse for taking a chance on Gunther.

She never expected the video to reach that many people across the internet, but she hopes it will encourage others not to give up on pets with physical impairments.

"We had no background in rehabbing animals, and weren't sure if we could help him, but we did it and others can too. I think it also just shows the determination that dogs have too," she told Newsweek.

"We are just so lucky to have Gunther. We had no idea we would be bringing him home that day, but he has been the sweetest and most well-behaved boy since the day we brought him home. He will play fetch all day if you let him, and he takes his ball everywhere with him."

Since going viral, the TikTok video has amassed over 100 comments from amazed social media users. One comment reads: "Thank you for caring for him."

Another TikTok user wrote: "Thank you for saving this baby!"

While another person added: "Awwww, he grew to be so handsome."

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