'Everybody loves an underdog', the saying goes, but nobody loves this underdog as much as his owner, Amy Butler.

Zorion, which means 'happiness' in Basque, is a three-legged kelpie from the Sunshine Coast that is impressing judges and spectators across Australia.

He and Butler have been competing in agility and obedience competitions for the past year, winning titles such as Community Champion Dog, Jumping Dog Excellent and Rally Obedience Dog (Advanced).

Earlier this year Zorion made the finals in the Australian National Agility Competition out of a class of 47 dogs.

What's most impressive about Zorion is the fact that, despite his handicap, the five year old wonder dog competes alongside dogs of all abilities and with all four legs.

Butler says she is incredibly proud of her beloved pet.

"He is the only three-legged dog I've seen competing in Queensland," said Butler.

"I know there's one down in New South Wales competing but we haven't come across it, and I think I've heard down further south there's another three-legged dog competing. He is in his class with four-legged dogs and in some of his classes he's beating them all."

Despite his growing success, Zorion has experienced many challenges since his early youth.

In April 2010, Zorion jumped unexpectedly from a parked ute, hitting the back tailgate and landing awkwardly.

"I didn't see him land but he jumped out the back of the ute after I had unchained him, before I could drop the tailgate," said Butler.

"As soon as he hit the ground he screamed and I had a freak-out, thinking 'oh god, he's broken his leg."

A visit to the vet and multiple x-rays showed that Zorion, while escaping a broken leg, had a dislocated hip and a chipped femur.

The then eight-month year old pup underwent a femoral head ostectomy where vets removed the head of the femur from the hip socket.

"In theory, it heals up as a ball of scar tissue in the hip socket and can move like a normal joint," said Butler.

"He was eight months old when he did that – he was still growing, so his femur was still growing."

The operation was unsuccessful when, five weeks later, Zorion hurt his leg again and x-rays confirmed that the femur had not healed correctly due to his growth.

"Options then were that they could go back and take more off the end of the femur, but there was no guarantee that it'd work," said Butler.

"We could put him on painkillers and see how he coped with it, or we could amputate."

Seeing amputation as the lesser of two evils, Butler chose to amputate, changing Zorion's life forever.

"We put him on painkillers for the week leading up to the amputation and, yes, he was running around on four legs when he was doped up to his eyeballs on painkillers," said Butler.

"As soon as those painkillers were off he was in so much pain. So amputation was the best option."

Zorion was back on his (three) feet soon after, swimming and chasing cattle.

Noticing his athletic ability, Butler began training Zorion in obedience in 2011 and joined the Lockyer Valley Dog Obedience Club.

"Someone said, 'you've got a kelpie, you should try doing agility.' I said, 'yeah, okay, we'll give it a go.' So, I started doing the basics with him and he picked it up so quick, and he loved it," said Butler.

"When I moved to the Sunshine Coast I made friends up here and they said, 'you should keep going with it', and so I did. I ended up going down to Caboolture Dog Obedience Club to continue doing agility training down there."

Butler says she was always conscious of Zorion's abilities, making sure she was not overworking him.

"My vet was fully aware with what we were doing and she supports me and understands that I know my dog's limits, and I'm not going to push him past what he can handle," said Butler.

"I think it [agility] built up his confidence in jumping, because he used to be not as confident, like even just jumping into a car or jumping up onto my bed or onto the couch. So I think starting doing agility training has built up his confidence in himself - he's practically fearless when it comes to jumping now."

While experiencing success at competitions and being supported by their current dog club, the Caboolture Dog Obedience Club, Butler says that she has been the subject of criticism.

One club insisted that a letter from Zorion's vet would need to be written, confirming his ability to participate.

"I showed this specific club that letter and they said, 'okay, that's fine', and then the next day I had a phone call from my vet saying that a lady from that club rang her and questioned her about the vet letter and basically demanded that she retract the letter," said Butler.

"So I called the club and was like, 'I'd like a letter of apology to my vet because that is highly inappropriate.' Needless to say, I did not get one."