LOUISVILLE, Ky. (WDRB) — The sun will be shining bright on Churchill Downs for the 141st running of the Kentucky Derby on Saturday, but more than that, it has shone favorably on the sport this spring.

In recent years, the Derby has all too often lost some of its most prominent contenders to injury before the call to post. This year, however, big names have arrived from all parts of the country to form what many are hailing as the deepest Kentucky Derby field in nearly two decades. On a day when a welterweight fight between Floyd Mayweather and Manny Pacquiao has drawn the attention of millions, the Derby is a matchup of heavyweights.

Bob Baffert, who trains both morning-line favorite American Pharoah and second-choice Dortmund, says the competition will be fierce.

“When I won with Silver Charm in 1997, that was a great field,” Baffert said. “This looks like the deepest field since then. It's like the NCAA Tournament, where every region has sent its best, and they haven't really faced each other. And until you see them out there together, you don't know whether Duke or Wisconsin or Kentucky is really the best team.”

American Pharoah, the favorite, lost in his first start and has won all four of his races since, by a combined margin of 22 1/4 lengths. In his last race, the Arkansas Derby, he demolished the field by eight lengths and jockey Victor Espinoza never pulled out his whip, never slapped the colt, just picked up his reins and took off.

“He's the real deal,” longtime trainer D. Wayne Lukas, who has Mr. Z in the Derby, said. “He's got all the elements you need. He has the style, the fluid movement, and a devastating kick. He's looked special from the first time I saw him.”

Owned by Ahmed Zayat, a native of Egypt who has been involved in the sport for a decade and had a handful of Derby disappointments, American Pharoah cemented his status as favorite with a 5-furlong work of 58 2/5 seconds at Churchill Downs that wowed onlookers.

History wasn't so kind to American Pharoah in the post position draw. He drew the No. 18 post, then was bumped down to No. 17 by a scratch. No horse has won the Derby from the No. 17 post.

But his versatility and tactical speed left Baffert satisfied with the outside post, and he trusts two-time Derby winner Victor Espinoza with the ride.

Espinoza, who won the Derby and Preakness a year ago with California Chrome and with War Emblem in 2002, learned to maneuver through traffic in as difficult a set of circumstances as there may be in the world — driving a bus in Mexico City. Having twice won the first two legs of racing's Triple Crown before falling short in the Belmont, Espinoza says this may be the best colt he's ridden.

But Espinoza and American Pharoah have keen competition, starting with his stablemate, Dortmund, who has never lost. Like his sire, Big Brown, he enters the Derby unbeaten, his last win a 4 1/2-length victory in the Santa Anita Derby.

Dortmund has impressed onlookers in Louisville with his size — he's 17 hands tall. Taller than Secretariat or Man o' War (16.2 hands), he has used his long stride to overpower challengers, and is coming off his most impressive race.

Dortmund was bred in Kentucky by Emilie Fojan's small operation in Lexington. Her fiance and business partner George Brunacini was killed when Comair Flight 5191 went down just after takeoff on August 27, 2006. It was a struggle to keep the farm going after he was gone. One of the mares they'd argued about, Our Josephina, was one he'd wanted to sell. She argued they should keep her. They kept her. That mare gave birth to Dortmund.

He's generally viewed to have faced tougher competition than American Pharoah, but a look at their last preps is instructive.

American Pharoah ran 1 1/8 miles two-fifths of a second faster than Dortmund, but was never asked to kick into his highest gear, while Dortmund got the whip several times heading into the stretch.

Third choice in the morning line is Carpe Diem, trained by Todd Pletcher. He's won 4 of 5 career starts and is coming off an impressive win in the Blue Grass Stakes at Keeneland three weeks ago. But Carpe Diem, who likes to run near the lead, drew the No. 2 post, a difficult spot in a 20-horse field.

Right beside him is co-fourth-choice Materiality, also trained by Pletcher. He's 3-for-3 lifetime and put up one of the most impressive speed figures of the season in winning the Florida Derby. He's also looking to buck history, seeking to become the first Derby winner since Apollo in 1882 to win the roses without racing as a 2-year-old.

Firing Line, with Hall of Fame jockey Gary Stevens, is the co-fourth-choice. He won the Sunland Park Derby last time out after twice finishing just a head behind Dortmund in stakes races.

“Any one of these, most of the past several years, would probably have come in here as the favorite,” Lukas said.

And some of the long shots carry impressive credentials. International Star, trained by Mike Maker and owned by Louisville businessman Ken Ramsey and his wife Sarah, has won five times in nine career starts and amassed $1,101,979 in purses.

Frosted, winner of the Wood Memorial, posted the fastest speed figure of any Derby hopeful in his last race, but is 15-1 in the morning line, as is Richard Violette's Upstart, winner of the Fountain of Youth Stakes before losing to Materiality in the Florida Derby.

The race will gather four of the trainers who have helped shape the event for 25 years. Baffert is seeking his fourth winner. Lukas, at age 80, already has won four. Nick Zito reached the field with a scratch on Thursday, and will send out Frammento, a closer who will go off at long odds. But that has never bothered Zito.

“We're in post 20,” Zito said. “But that's better than Post Zero. He's definitely a distance horse.”

And there's Pletcher, who will start three in the Derby. He's won it only once, but has had 40 starters.

Also looming among the long odds is an import from Dubai. Middle Eastern racing interests, who have helped bolster the sport considerably over the past two decades, have been trying just as long to win the Derby, without success. This year South African trainer Mike DeCock brings in Mubtaahij, a talented Irish-bred colt who has won four of his last five races, including the $2 million U.A.E. Derby, by an impressive eight lengths.

In recent years, the Derby has, because of its prominence in the sport, drawn headlines when there has been controversy — over use of race-day medications, or treatment of the animals.

This year, it's the accomplishments of the thoroughbreds that will draw the attention of a crowd of better than 150,000 on track and millions on television on what is expected to be a sun-splashed day at Churchill Downs.

It's been a while since horse racing celebrated a golden age. For one afternoon in Kentucky, at least, its fans may be treated to a throwback edition of the sport's most famous race.

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