Just a couple of weeks on from American Pharoah ending a 37-year Triple-Crown drought, fellow Kentucky Derby winner California Chrome will attempt to achieve something not done since 1929.

In 1929, as the world was bracing for the Great Depression, the Kentucky Derby winner of the previous year, Reigh Count, was on his way to England to prove himself the best horse in the world.

He probably fell short of confirming himself the best in the world, but after losing his first couple of starts on British soil he did manage to land Epsom's Coronation Cup.

Since 1929 no horse trained outside of Europe has managed to win what we now call a 'Group One' race over 2000m or further - that's a drought almost 2.5 times longer than the Triple-Crown drought recently snapped by American Pharoah.

On day two of the Royal Meeting at Ascot this year there will be three horses out to break this drought. Joining last season's Kentucky Derby winner California Chrome are the Aussie Criterion and Spielberg from Japan.

“I’ve been watching the Aussies come here and do so well with our sprinters," David Hayes, trainer of Criterion, told the media at Newmarket.

“I always thought if I had a horse that might be good enough it would be great to take the English on at their own game, which is middle distance.

“The Prince Of Wales’s Stakes is going to be a very hard task, with a tough international field but all I can say is Criterion is very healthy and I have been very happy with his work.

“The horse had a look around Ascot last Tuesday. I was pleased with him, and young Chad Schofield, who rode him, said he handled the undulations very well."

Ratings will show that the trio of travellers are good enough to be very competitive, but that's in their own backyards.

Beating Europe's best on their home turf (the word 'turf' being particularly relevant/daunting in the case of California Chrome) is going to require a peak performance - probably better still - outside of the conditions that they have produced on in the past.

California Chrome faces the different race shape of turf racing. Criterion has to cope with Ascot's undulations having done his racing on the flat tracks of Australia, and Spielberg comes off the flint-hard turf of Tokyo where his best has come racing among the hustle and bustle of the big fast-moving fields that are commonplace there.

The current market sees the trio a (roughly) 25 percent chance of following in the footsteps of Reigh Count, albeit some 86-years on.