It’s the most remarkable bond formed by an unlikely pair: An Australian ultra-marathon runner and a scruffy desert dog.
Through one of the most gruelling foot races on Earth, in one of the most isolated locations, a stray chihuahua cross was about to change Dion Leonard’s life forever.
On the first day of the week-long race aross China’s desolate Gobi Desert, Dion noticed the stray wandering around the camp.
But when the race began and the 100 competitors took off from the starting line, Dion was surprised to find the dog running alongside him.
“This little dog’s running beside me and looking up at me and I’m waiting for her still to peel off, 50, 100, 200 metres,” Dion told Sunday Night reporter Steve Pennells.
“She’s keeping up with me, she’s actually running a little bit ahead and looking over shoulder at me.”
For each leg of the exhausting race, the little dog - who Dion named Gobi after the desert they were running across - followed him stride-for-stride.
After the pair finished the race together in second place, Dion knew his adventures with Gobi weren’t over. He made it his mission to bring his new best friend back to his home in Scotland.
But while Gobi was in quarantine in the Chinese city of Urumqi, she went missing.
A social media campaign to find her quickly went viral and Dion was soon being bombarded with 200 leads daily – but each tip-off seemed to be a dead end.
“I really was at the lowest I’ve ever been, emotionally wrecked,” he said.
“To actually know I had let her down was something I would have to regret for the rest of my life.”
After 10 long days, Gobi was found by a family on the other side of the city – but during her days on the street she had taken a beating.
She required surgery to repair her broken leg, but with the best care possible and several weeks of rest, she made a full recovery.
When she was finally cleared to fly back to Scotland with Dion, it was an emotional end to his longest race yet.
"That was the best finish line ever," he said.
"This has been the best reward, the best race medal."