When Sheikh Mohammed bin Rashid al Maktoum set his sights on the U.S. Triple Crown series, many Americans viewed his Godolphin Racing Inc. as an unstoppable juggernaut. The sheikh from Dubai has the biggest, most lavish racing operation in the world and the petrodollars to buy almost any top thoroughbred he covets. After dominating the English classic races year after year, he was looking for new worlds to conquer.

No one familiar with Godolphin's impressive European record could have anticipated the results of its U.S. invasion this spring:

Prado's Landing finished a distant last in the Blue Grass Stakes at Keeneland.

Worldly Manner, the star of the Godolphin contingent, challenged for the lead in the Kentucky Derby before fading to finish seventh. He came back in the Preakness and lost by 36 lengths.

Aljabr, who was also entered in the Derby, went lame before the race and was scratched.

Comeonmom, the stable's hope for the Belmont Stakes, finished a distant last in the Peter Pan Stakes Sunday. In the wake of his defeat, the Godolphin operation is quietly sending all of its U.S. runners to its base in England.

Why did this venture fail so miserably? Now that we're no longer blinded by the Godolphin mystique, the reasons are easy to see.

Godolphin had achieved its greatest successes by bringing top English prospects to Dubai, training them there through the winter and sending them back to England, where they would immediately win major stakes races. Sheikh Mohammed made believers of all the skeptics when Lammtarra, unraced as a 3-year-old, won the demanding Epsom Derby. If a colt could win at 1 1/2 miles after a long layoff, shouldn't one be able to do the same in the 1 1/4-mile Kentucky Derby?

Not necessarily -- because there is a fundamental difference between racing on dirt and turf. Races on the dirt are typically fast-paced and intensely competitive from start to finish. In long-distance grass races, by contrast, the field usually lopes along for a mile or so before accelerating in the stretch. Horses need less conditioning to compete in a long turf race, and it is not uncommon to see horses perform well in them after extensive layoffs.

Trainer Bill Mott has a grass specialist, African Dancer, who in each of the past four years has started his campaign by running 1 3/8 miles or more after a layoff of many months. He has finished first or second each time. But even a great trainer like Mott would rarely try to manage a dirt runner the same way. Mott never ran his champion Cigar in a 1 1/4-mile race after a layoff of even two months.

If it is hard for an experienced older horse to win a distance race on the dirt after a long layoff, the feat is vastly more difficult for a youngster who has never run a long race in his life. Despite the training they had received in Dubai, the Godolphin 3-year-olds were woefully unprepared for the rigors of American dirt racing.

Godolphin's failure wasn't due only to the shortcomings of its training strategy. Its judgment of horses often was badly flawed.

Spending $5 million for Worldly Manner was extravagant but not irrational; the colt looked like a potential champion and, indeed, might have been good enough to win the Derby with more orthodox preparation. But some of Godolphin's other thoroughbred purchases were incomprehensible.

In last fall's Remsen Stakes at Aqueduct, a fast early pace took a toll on all the speed horses, enabling Comeonmom to rally and win by a nose in unimpressive time. His Beyer Speed Figure, earned under optimal conditions, was a moderate 94 -- the only time he had run a number better than 80. Most handicappers would have been eager to bet against him the next time he ran. Yet Godolphin paid a laughable $3 million for the colt, who was idle for six months before losing the Peter Pan Stakes by 25 lengths.

Prado's Landing wasn't one of Godolphin's lavish purchases; he had won only a maiden race (with a figure of 75) when the sheikh acquired him last year. If the colt had been laid off for months and entered in a bottom-level allowance race at Pimlico this spring, he would have been no cinch. What did Godolphin expect by entering him in the $750,000 Blue Grass Stakes? Did it misunderstand his limited capabilities? Did it think that the training regimen in Dubai transformed the colt from a Maryland allowance runner into a stakes horse?

When Godolphin launched its assault here, many of us were mesmerized by the stable's European feats and assumed that there might be indeed some magic associated with the Dubai operation. Now it's obvious the experts in the desert didn't have a clue about the nature of U.S. dirt racing. After their failures this spring they ought to understand what Americans do. The 3-year-old classics are extraordinarily difficult to win; they challenge the skill of the greatest trainers and frustrate the most ambitious owners. Not even an owner with the vast wealth of Sheikh Mohammed can readily buy success in the Triple Crown.