Imagine if Theo Walcott had not merely gone to the World Cup on holiday, but had won the Golden Boot, and you will have some idea of how one of the most astonishing stories of the sporting year is unfolding in the United States.
A year ago last week, Julien Leparoux had never ridden in a race of any kind. On Saturday, he won the Beverly D Stakes at Arlington. It was his first Grade One success. It was also his 286th winner this year, and a ride flavoured by genius.
There is a tangible sense here that Leparoux, who emigrated from France just three years ago, stands on the brink of one of the great careers in Turf history. After big races at Arlington, it is traditional for the winning jockey to give away his goggles as a souvenir for the children who gather shrieking and waving by the unsaddling enclosure. Leparoux duly placed his into one of the little hands stretched between the railings, and turned away with a smile. A woman promptly reached down and snatched them away from the horrified child, raising them aloft in shameless elation.
Leparoux had won the race on a filly trained by his mentor, Patrick Biancone - respected throughout the racing world as a sorceror not only with horses but also with riders. In their apprenticeship, he tutored four of the best French jockeys of recent years: Dominique Boeuf, Eric Legrix, Gerald Mossé, Olivier Peslier. "All very good riders," he said. "Yet I always say that it would have taken the four of them together to make one perfect jockey. And this one, Julien - he is like all of them together. He has everything."
In the Beverly D, Leparoux rode with epoch-making audacity, detaching his filly from the rear of the field and sitting motionless until the home turn. As the leaders faded, he came scything down the centre of the track and won going away. Asked if Leparoux had been following instructions, Biancone puffed out his cheeks. "It's the first time I have ever had a jockey I never tell how I want a horse ridden," he said. "He has too much talent for me to be interfering."
When Jerry Bailey retired during the winter, he appeared to have ended a golden age in American riding, one that had embraced Gary Stevens, Pat Day, Chris McCarron, Laffit Pincay Jnr. Yet the vacuum appears to have been filled overnight.
"Whatever they tell you, it's all true," another trainer, Eoin Harty, said. "This kid is the complete package. Never gets rattled, always in the right place, always saves something, and finishes. There are a lot of good young riders around but nobody can touch him. I saw a replay of his first win the other day, and it looked more like his 8,000th."
That was in Saratoga, on 18 August last year - only his third ride. After a couple of dozen winners at lesser tracks, the word got out that his claim amounted to larceny. In the new year, based at Turfway Park, he shattered the meeting record with 167 wins.
Even then it was still possible that Leparoux was just the latest "hot bug" - the idiom here for an apprentice, whose entitlement to deduct weight is signified by an asterisk, or bug, on the racecard. Turfway is a racing backwater. The competition would be more exacting at Keeneland.
But Leparoux tied as leading rider there with Rafael Bejerano, an established star. And now, three winners on his day trip to Chicago aside, he is back at Saratoga - the ultimate crucible on the American circuit. "This is the next step, the next level," he said, taking some shade outside the clapboard jockeys' room during another searing afternoon. "It's a tough meet. Almost all the best jockeys are here. But winners give you confidence, give you hunger, and of course encourage more people to use you.
"It's true, I came in at a good time. There is a new generation of riders coming through. If those guys were still around, Jerry Bailey and so on, it would be harder to get on the good horses. There are still some very big names, people like Johnny Velasquez, and a lot of very good younger ones too, like Rafael Bejerano and Javier Castellano. But I've surprised people, for sure."
The bewildering speed of his emergence has not exposed some gawky adolescent. At 23, he has due self-possession. Though he has been around horses all his life - he was riding showjumpers at 11, and his father was assistant trainer in one of the minor Chantilly stables - Leparoux did not ride a thoroughbred until he was 18. A couple of years later he joined a friend working for Biancone, and began riding trackwork. His employer, a man of instinct and imagination, was soon intrigued. But as Leparoux himself put it: "If you are good in the morning, it does not mean you're going to be good in the afternoon."
A mild, courteous young man, his light, elegant movements untainted by swagger, Leparoux leaves the flamboyance to Biancone. "Well, Mr Biancone - he's the boss, first and foremost," he said. "But the stable is also my family. It's a big team, we work together, and I am always especially happy when I win races for them. They are the best type of friends: they keep my head on my shoulders. They don't tell me what I want to hear, but what I need to hear."
Though he can still claim for another month, Leparoux is routinely contesting stakes races on level terms. "Of course, there's a big difference in my riding from a year ago," he said. "I have improved in every way. How do I need to improve now? In every way. Maybe I'm a bit stronger, but the most important thing is experience - you grow richer in experience every day, and that will always be true."
Biancone commends the caution of his protégé, but feels absolved of any himself. "A prodigy," he said. "Just a natural. He gets a horse to put the maximum into the race, but never takes anything away from the horse. That's very important, for the long term - that's why trainers will want to use him.
"He just has this gift. That's all. You might as well ask why Tiger Woods is Tiger Woods. Or why Mozart was writing symphonies at seven. Of course, that did not mean Mozart did not have to work hard afterwards - and Julien is as stable and dedicated as he is talented. But his gift is not something you try to explain. I tell him: 'don't ask yourself why you're doing something. Just do it'."