updated 7:47 p.m. ET June 4, 2008

NEW YORK - Edgar Prado is looking for his own triple of sorts in Saturday’s $1 million Belmont Stakes, as in three times a Triple Crown spoiler.

The Hall of Fame jockey will be aboard Casino Drive in his bid to upset Kentucky Derby and Preakness winner Big Brown and extend thoroughbred racing’s Triple Crown drought to 31 years.

Prado did it twice before, beating War Emblem with Sarava in 2002 and topping Smarty Jones with Birdstone in 2004. That’s two of the past three Triple tries, and he did it with two long shots.

This time, Prado will be riding perhaps the biggest threat to Big Brown, the 2-5 morning-line favorite, with Casino Drive the 7-2 second choice in the field of 10 3-year-olds.

Nobutaka Tada, racing manager for Casino Drive owner Hidetoshi Yamamoto, said Prado was chosen not because of his role as a spoiler but due to his patience — something that is reflected in the unique way the colt is being prepared for the 1½-mile Belmont.

And Prado just might have added incentive: He was supposed to ride Big Brown, but because of an injury and a new owner he was bypassed for Kent Desormeaux.

“I have to go out and do my job and the people I have to respond to are the Japanese people who will give me a leg up,” Prado said. “I’ll do everything I can to win.”

Prado has said he’s still not sure why he didn’t get a shot on Big Brown, especially since he rides many of trainer Rick Dutrow Jr.’s horses. But on a rainy Wednesday morning, after watching Casino Drive finish off a 60-minute walk around Belmont Park before a jog around the track, he sounded ready to move on.

“Unfortunately, destiny happened and I was not able to be on him,” he said. “It was not meant to be because it happened twice, once in Saratoga and once in Florida.”

Two days before Big Brown’s career debut last summer, Prado broke his right ankle in a spill at Saratoga. Jeremy Rose was chosen by original trainer Patrick Reynolds to replace Prado, and Big Brown won by 11¼ lengths.

Michael Iavarone and Richard Schiavo’s IEAH Stables then bought a 75 percent interest in the colt from Paul Pompa Jr. for about $3 million and sent Big Brown to Dutrow.

Late last year, with Prado recovering from his injury, Big Brown was sidelined with an abscess in the sole of his left front foot, then missed another 45 days early this year with the same problem to his right front foot.

Prado worked out Big Brown three times at Palm Meadows training center in Boynton Beach, Fla., prior to the colt’s second career race, at Gulfstream Park on March 5. But Iavarone had dinner one night with Desormeaux, and that was that.

“I just felt Kent fit this horse. He’s aggressive, he’s strong, and he’s riding really well,” Iavarone said. “Edgar made it clear he was pretty upset. But this is not a knock on Edgar. He’s fabulous. But we pay the bills, we own the horse and we have the right to make the decision.

“It’s not like we made a mistake, but I know Edgar’s going to be trying hard to win.”

Prado, who won the 2006 Derby with Barbaro, has won more than 6,000 races. Among them are more than 265 for Dutrow, and he will be aboard the Dutrow-trained, IEAH-owned Benny the Bull in the True North Handicap on the Belmont Stakes undercard.

“We’ve talked about it and turned the page,” Iavarone said. “At least I hope we have.”

Dutrow was not thrilled with the decision.

“Prado’s my man,” he said before the Preakness. “I love him. I was disappointed when Mike wanted to do that. But Kent’s a good man and he deserves it.”

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