O'Brien dreaming of historic Kentucky Derby success with Mendelssohn

Preview: USA, Saturday 11.50pm BST (live on ATR)

Churchill Downs:Kentucky Derby (Grade 1) 1m2f | dirt | 3yo

A European-trained horse has never won the Kentucky Derby – but then again, not since Arazi in 1992 has one arrived with such fanfare beneath the iconic Twin Spires for America's greatest race.

Arazi, though, finished a dismal eighth. Can Mendelssohn succeed where the French superstar flattered to deceive?

For all that the son of Scat Daddy looked a world-beater when finally being switched to dirt in Dubai, let no one be in any doubt about the magnitude of the task ahead.

Make no mistake: even allowing for the formidable achievements of Aidan O'Brien and Ryan Moore – in Kentucky rather than partnering one of the Ballydoyle 2,000 Guineas horses at Newmarket – victory for Mendelssohn in the $2.2 million event might top the lot.

History, though, tells its own tale. Despite the combined might of Coolmore and Godolphin having taken a few shots in the last couple of decades, Bold Arrangement's magnificent second to Ferdinand in 1986 for the pioneering Clive Brittain remains the best ever placing achieved by a transatlantic visitor.

Few, though, have landed in Louisville with credentials akin to Mendelssohn. A $3 million yearling, Mendelssohn's pedigree screams 'dirt', and he has been targeted for the 'Run for the Roses' ever since he won the Breeders' Cup Juvenile Turf at Del Mar last year – a performance that amply demonstrated his ability to travel and run on Lasix.

Note, too, he had no fewer than three 2,000 Guineas contenders behind him at Del Mar, including Craven and Greenham winners Masar and James Garfield.

A reappearance Listed victory at Dundalk blew away the cobwebs before he was finally switched to dirt with that spectacular 18-length victory in the UAE Derby.

Taken at face value, that was virtually off the charts in handicapping terms – but can anything on the idiosyncratic Meydan dirt surface really be trusted?

What is more, Mendelssohn faces what is said to be the hottest Derby fields in years, his status among the locals being not far off a 'mystery horse' against at least one more potential superstar in Justify.

Words of wisdom: Aidan O'Brien surrounded by media at Churchill Downs before Mendelssohn's Kentucky Derby bidCredit: Getty Images/Michael Reaves

Although O'Brien is painfully aware of the alien nature of the assignment – remember, his champion two-year-old Johannesburg was only eighth here in 2002 after winning the Breeders' Cup Juvenile the previous year – he seems happy enough with Mendelssohn's progress.

“He travelled over well and Pat Keating [travelling head lad] and the lads who went with him have been very happy with him since he got there,” he said. “He's cantered on the track and is in good form.

"He’s a very special-looking horse physically and, with his pedigree, he came to us as a top-rated horse. Usually those horses, if things go right, they have a big shot."

AIDAN O'BRIEN'S KENTUCKY DERBY RECORD

2002 Johannesburg 8th

Castle Gandolfo 12th

2011 Master Of Hounds 5th

2012 Daddy Long Legs DNF

2013 Lines Of Battle 7th

O'Brien added: "We were very lucky to get the two runs into him this season and he's kept progressing from race to race. We were thrilled with him at Dundalk and then he improved again in Dubai.

“Everything has gone to plan so far this year and all has gone well since his win in Dubai, where he was very effective on the dirt and got the trip well. We haven’t done a lot with him since but he's ready and we’re looking forward to what will be a big challenge.

"It would be something we couldn’t really dream of, to win this race. We feel so privileged to be here and have a horse who can compete."

The weather adds another imponderable, with a 40 per cent chance of rain. Not that it would worry connections of much vaunted Justify (Bob Baffert/Mike Smith), who has already won on mud at Santa Anita, where he took his unbeaten record to three last time out by beating Derby rival Bolt D'Oro (Mick Ruis/Victor Espinoza) in the Santa Anita Derby.

Another son of Scat Daddy, Justify is a hugely imposing physical specimen who has produced a series of intimidating speed figures.

However, he is short on seasoning and, like Arkansas Derby victor Magnum Moon (Todd Pletcher/Luis Saez), is aiming to become the first horse since Apollo in 1882 to win without having raced as a two-year-old.

“The Apollo curse is something I don’t even think about and it’s something that’ll be broken, whether it's this year or another year,” said Baffert, who also runs Solomini (Flavien Prat) as he bids for his fifth success.

Justify's draw in gate seven means Smith will surely have little option but to send him close to the front rank. The danger is that there is a lot of speed signed on in opposition.

Elsewhere in a red-hot field, Todd Pletcher saddles four, headed by Florida Derby victor Audible (Javier Castellano). His others include the unbeaten Magnum Moon, Vino Rosso (John Velazquez), who beat Godolphin's Enticed (Kiaran McLaughlin/Junior Alvarado) in the Wood Memorial, and Louisiana Derby victor Noble Indy (Florent Geroux).

US champion trainer Chad Brown says Good Magic (Jose Ortiz) is “in the zone” after regaining his form in the Blue Grass Stakes.

Winner of the Breeders' Cup Juvenile last term, he looks primed for a top effort on the third run of his form cycle.

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