The ultimate accolade for a horse has nothing to do with prize money or trophies, nor much to do with records in a book. Only when jockeys are moved to forsake the comforts of their weighing room and troop down to the paddock out of a combination of curiosity and admiration can a horse truly be classed as a superstar. When Curlin, the US Horse of the Year, made his long-awaited reappearance in a low-key race in Dubai last month, there were more jockeys than runners in the parade ring.

“They just wanted to see what all the fuss was about,” said Seb Vance of the Dubai Racing Club. The fuss was all about a flashy chestnut with an imposing presence who had ended an unforgettable season in the States.

Through the US Triple Crown – the Kentucky Derby, the Preakness and the Belmont – Curlin had battled with Hard Spun and Street Sense, with honours pretty well even until Curlin asserted his superiority like a true champion in the Breeders’ Cup Classic at a sodden Monmouth Park in October.

In the UK, the race will be remembered for the death of the brilliant George Washington, but Curlin pulverised the field under Robby Albarado, confirming the rise of trainer Steve Asmussen, who has been recalibrating the statistics in US racing over the past five years with the same authority as Martin Pipe here.

In 2004, Asmussen, the younger brother of Cash, one of the finest jockeys of his generation on both sides of the Atlantic, recorded a shattering 555 winners. But, like Pipe, the experts refused to be dazzled by figures alone. Asmussen, they said, could not be considered a top trainer until he had won a Triple Crown race and a Breeders’ Cup. He has now done both, ironically at the end of a season that began with him serving a six-month suspension for a doping offence.

On Saturday, Curlin will put his growing reputation to the test in the Dubai World Cup, at £3m the richest race on the international calendar. It is a surprise that Curlin has been kept in training for his four-year-old career, even more of a surprise, given the dominant economics of the breeding industry, that his major owner, Jess Jackson, a wine-grower in California, says the prime reason for prolonging his career was the sport itself. Even if only partially true – Saturday’s first prize of £1.8m is a decent incentive as well – Curlin’s presence in Dubai has created the sort of rustle normally reserved for Oscar ceremonies.

Curlin has some work to do to match the star quality of Cigar or Dubai Millennium in the land of Godolphin, but he has the potential – and like so many of the American horses, there is a story to tell. This one involving a court case where two of his original owners are due to face trial for fraud. It is alleged that lawyers Shirley Cunningham Jnr and William Gallion bought Curlin with funds from a lawsuit that should have been used for “charitable purposes”. As ever in US law, the case has dragged on, but racing was more stunned by the fact that Curlin was bought initially for no more than £25,000. That was the real steal, surely.

Asmussen’s association with him began at Gulfstream Park, where he had gone to scout another horse. He was so transfixed by Curlin’s debut that, by sundown, he had persuaded a three-man syndicate headed by Jackson to buy 80% of the colt for £1.7m. The other 20% is with Gallion and Cunningham.

Scott Blasi, Asmussen’s No 2, is a proper midwest horseman, like his boss. He was brought up on a farm in southeast Kansas, where his father trained quarter-horses. Twelve years ago, he found a fellow traveller in Asmussen, who had been a low-rank apprentice jockey before turning to training in 1986, round Lone Star Park in Texas and Sunland Park in New Mexico.

“We both started at the bottom, $5,000 claimers in downtrodden tracks, we’ve done that,” says Blasi. “It makes you appreciate all the more when a horse like this comes along. When you come from the bottom up to the top, you see a lot of things and you learn quickly.” Asmussen quickly got a reputation for being an ambitious young trainer and a single-minded competitor. From Lone Star Park, his training operation grew from coast to coast until he now has 300 horses spread across six different training bases. In working to a scale unprecedented in US racing, Asmussen did not endear himself to the establishment or the press. One journalist called him “confrontational, contentious, abrasive, brash and arrogant”. Asmussen can still quote the whole sentence. “It’s not how you want to be described,” he says, “but I do know who I work for and I do know they are people with certain expectations.”

In Curlin, Asmussen and Blasi have found a horse to take them to a new level. “Curlin’s a true professional,” says Blasi. “When he steps on the track, he goes to work. I’m learning to relax too and be patient with people. We don’t want to hide away, we want people to enjoy Curlin as much as we do.”

With Jalil and Asiatic Boy in the field on Saturday, Curlin will not have everything his own way. Racing, as Blasi points out, does not work to order, but the weighing room will echo like a cavern if Curlin lives up to his billing.