In his formative years, Casey Stoner would think nothing of travelling 2,500 kilometres from his home in Australia to go dirt-tracking, and his journey from Kurri-Kurri to the MotoGP title has been just as arduous, taking in the sale of the family farm, a caravan near Wigan and eight mesmerising victories in one of the most surprising seasons of modern times.

Despite an impressive win in Portugal last weekend, Valentino Rossi has been intimating for months that Stoner is ready to take the championship. Colin Edwards, Rossi’s Fiat Yamaha teammate, agreed. “Casey can stand toe to toe with Valentino and beat him,” he said candidly.

Yesterday, Stoner had to finish ahead of Rossi in the Japanese Grand Prix at Motegi to become the second-youngest champion. He took advantage of a bizarre race, the first wet-dry one to allow riders to change to slick tyres, to finish in a modest sixth.

Rossi, who tried to stay out longer than Stoner before coming in, only to suffer more trouble and later run off the track and back into the pits, was a distant thirteenth. “Congratulations to Casey,” the five-time champion said magnanimously. “I am very flattered that he made a dedication to me on his victory T-shirt because if someone else has to win then I am glad it’s one of my fans. He is a great rival and I hope that we can continue this rivalry into the future.”

Stoner’s rise has come with attendant caveats about the superiority of his machinery. “First it was the power of the Ducati, then the Bridgestone tyres, blah, blah, blah,” Stoner said. “I think we’ve proved a lot of people wrong this season. This is unreal.”

To cap a great day for Ducati, who celebrated their first riders’ title and the first by a European manufacturer for 33 years, Loris Capirossi, Stoner’s teammate, won the race.

Stoner’s status as a prodigy - at 21 he is the youngest rider on the grid – reflects a past that saw him grow up fast. “When he was 4, a Japanese magazine asked him what he wanted to be and he said Mick Doohan,” his father, Colin, said. Stoner is now the third Australian to win the championship after Doohan and Wayne Gardner.

Stoner Sr had enough belief in his son to sell the family farm in Kurri-Kurri to travel to Britain, where the 14-year-old was deemed old enough to race on tracks. “It was hard in Europe because sponsors wanted European riders,” Stoner said. “And there was no shower in our caravan.”

He competed in the Aprilia Super-teen class and the British 125cc Championship before renting a bike to try his luck in Spain. He did well enough to catch the eye of Alberto Puig, the talent-spotter supreme who was already mentoring Dani Pedrosa, and a bond was formed. “We were camped out in Alberto’s yard for a couple of years,” he said. “We were like the gardeners living out the back.”

His progress was scarcely Rossi-esque. His first full year on the grand prix circuit saw him finish twelfth in the 250cc class and it was not until 2005, when he was runner-up to the then wunderkind Pedrosa, at the same level, that he began to become noticed.

Only “Fast” Freddie Spencer, the lustrous star from America’s Bible Belt, was a younger champion. Spencer won the title twice and retired at the age of 25, bereft of motivation and weighed down by injuries. Having spent years travelling dusty roads for dirt-track races and then living in a caravan with no shower, Stoner plans to clean up for significantly longer.

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