Mendelssohn departed Ballydoyle Stables in Tipperary on Monday and was expected on the grounds at Churchill Downs in Louisville, Kentucky at approximately 5.30pm local time.

(It was reported by local press on Monday evening that the flight carrying Mendelssohn was diverted from Louisville to Indianapolis due to an administrative issue. Mendelssohn was transported by horsebox on the 115-mile journey to Louisville but the diversion added almost five hours in total to his transport time.)

On Saturday the Aidan O'Brien-trained colt will attempt to become the first European-trained horse to win the Kentucky Derby.

At Churchill he’ll be under quarantine in Barn 17 – standard practice for horses shipping into the US – for a period of 48 hours and is expected to train for the first time at Churchill Thursday morning.

Each day this week I'll be posting Derby news here with particular focus on this exciting Irish challenger.

THE BREEDER

A saturating rain pelted the roof one day last week as Nancy Mitchell eased into her sun-room recliner facing a field a mares, Fred Mitchell took a spot on the couch for a rare quiet moment, Marty Buckner paid some bills and finished some paperwork and Ernie Ernst checked the weather via radar on his computer.

Just another day at Clarkland Farm in north Lexington in the heart of the Bluegrass? Maybe, but these are anything but average days for the family owned and run farm that goes back further than US Constitution or the Declaration of Independence.

The reason is Mendelssohn, the latest pride and joy to come off the farm that produced what rival operations might see as a disproportionate number of top-class racehorses throughout its history. Mendelssohn, Coolmore’s representative in this year’s Kentucky Derby, flies the flag for the Mitchells and Clarkland after topping the 2016 Keeneland September yearling sale at $3 million and winning the Breeders’ Cup Juvenile Turf and UAE Derby to earn his return trip to America.

Mendelssohn is a son of the late Scat Daddy out of Clarkland’s prized mare Leslie’s Lady, who delivered a filly by American Pharoah last week and is also the dam of multiple US champion Beholder and leading sire Into Mischief.

She’s one of the mares Nancy Mitchell kept her eyes on last week and the mare Fred Mitchell gives all the credit.

“Our biggest successes have come through Leslie,” Fred Mitchell said of the daughter of Tricky Creek, named Broodmare of the Year in 2016. “When she got Broodmare of the Year it was quite a satisfaction. It’s quite an honour. The things that have happened to Nancy and I and Clarkland don’t happen at small farms. We’ve been very fortunate.”

SEVENTH FOAL

The Mitchells are nothing short of fortunate to own Leslie’s Lady, a mare they bought for $100,000 in 2006.

Mendelssohn is her seventh foal and come Saturday could wind up her best yet, surpassing the brilliant four-time American champion mare who won two Breeders’ Cup races and earned $6.1 million.

The folks at Clarkland aren’t counting on that just yet, but they’re allowing themselves to dream.

“That’s what makes life go around on a farm, dreaming,” Fred Mitchell said.

Mitchell never imagined the colt he described as straightforward and never a problem as a youngster, would realise every commercial breeder's wildest fantasy when he went to the Keeneland September yearling sale in 2016.

Easily the talking horse of the sale, Mendelssohn was shown more than any horse Mitchell can remember during the week leading up to the auction. None of the pre-sale activity – inspections, radiographs or scopes – fazed the colt.

Just like he’s done on the racetrack, where he’s already won in Dubai on the dirt by 18 and a half lengths and the Breeders’ Cup Juvenile Turf at Del Mar, Mendelssohn handled it all.

“It’s really showing up now,” Mitchell said. “With what we he went through as a yearling and in the sales ring to now shipping from one continent to another and back, then going to another continent and back, he just takes it all in and he runs. A lot of horses that do that, they don’t run their race after they get shipped.”

FIRST DERBY

Fred Mitchell plans to be on hand when Mendelssohn runs in the 144th Kentucky Derby, amazingly his first time to see America’s great race with his own eyes.

“I haven’t been to a Derby and I’ve been here my whole life. Been to the Oaks, but not any Derby,” Mitchell said. “Usually we’d rather sit here in watch on TV than fight all the crowd. I always said the only way we’d go if it was something we raised, bred and sold.”

And one with a chance, which he believes is Mendelssohn.

“When you sell a horse for that kind of money you love to see him do well for whoever bought him, and he’s done more than we could have ever expected. And we hope he does more,” Mitchell said. “I thought with his pedigree and the individual, when you look at him he’s a breeder's dream. He had the most beautiful back leg on him and had a presence to him that you just love. It’s something you’d love to get back into your mares. I don’t know if we’ll ever be able to afford to breed to him, but we’d love to breed to him. He’s a special individual.”

READ TOM LAW'S DERBY DIARY EVERY DAY THIS WEEK IN THE IRISH FIELD