Youth is no barrier for Japanese invader aiming to conquer Ascot

It is not just Yoshito Yahagi who has experienced transformation since he was last in Newmarket. At 51, he returns as trainer of the Japanese Derby winner, Deep Brillante, an audacious challenger for the Betfair King George VI and Queen Elizabeth Stakes at Ascot on Saturday. The colt is lodging with Clive Brittain, just over the road from Geoff Wragg's old yard – where Yahagi once worked as a humble stable lad. A broader metamorphosis, however, reflects more favourably on his homeland than on his hosts.

Their roles seem to have been transposed. A parochial betting market dismisses Deep Brillante, yesterday trading at 18-1 with the sponsors. Not so long ago, however, Japan was herself the most insular power on the Turf. Nowadays, the Japanese are so confident in their performers – and, especially, their pedigrees – that a bonus of ¥50 million (£400,000) is offered to their Derby winner for any and each of four races he might add on a global stage: this one, the Breeders' Cup Classic, Dubai World Cup and Prix de l'Arc de Triomphe.

It was in the 2006 Arc that Deep Brillante's sire, Deep Impact, sought an earlier frontier. In the event, he could only finish third, but he has rapidly consolidated his stature since retiring to stud, Deep Brillante being among three sons to make the first four in the Derby.

It is unusual, however, for such an immature horse to travel here from Japan. Yahagi himself did bring a colt to the St James's Palace Stakes last year, but Grand Prix Boss did not show his form and Deep Brillante has only had six starts. "Grand Prix Boss was not as consistent," Yahagi said. "This is a big, strong, muscular horse, more powerful than most of the other good horses in Japan. Deep Impact's progeny have tended to be lighter types, suited by fast ground, but Deep Brillante won a Group race as a two-year-old in heavy going.

"We recognise we are setting him a tough task, as a three-year-old in summer, against some of the best older horses in Europe. But this experience will accelerate his improvement, both later this year and as a four-year-old. To win we must make history. But it is important, especially for our breeding industry, to show our horses all round the world."

The colt's jockey is Yasunari Iwata, who won the 2006 Melbourne Cup on Delta Blues. "I've ridden a lot of Group One horses," he said. "And this one is the most honest. We are here to win."

Turf account

Chris McGrath's Nap

Tamarrud (7.45 Epsom) Has started in handicaps off a very manageable mark, keeping on well off a quickening pace last time.

Next best

Pompeia (6.50 Doncaster) Made an excellent debut at Newbury last month, going close despite running green.

One to watch

Piri Wango (Ger Lyons) Coped well with the drop to 6f at Newmarket last week, finishing well after being set plenty to do.

Where the money's going

Or not – St Nicholas Abbey, 2-1 with some bookmakers, was yesterday trading at twice those odds with Betfair for the King George.