Incredible Luck Required Merely to <i> Be </i> in the Derby : Overview: The fact that most of the top 3-year-olds have made it to Louisville makes it a standout field.

The pitfalls between New Year’s Day and the first Saturday of May are everywhere--injury, illness, twist of fate, confrontation with the reality of limitation, human error. The combinations of those variables are infinite.

This, the harshest of racing’s realities, explains in part why no 2-year-old champion has won a Kentucky Derby since 1979. It explains why the mere presence of any of the 15 horses in today’s Kentucky Derby is a longshot. It also makes this field of 15 all the more remarkable. The only notable absences are Dehere, last year’s 2-year-old champion, who was injured while training for the Florida Derby, and Wood Memorial-winner Irgun, who suffered a minor hoof injury after arriving here for the Derby.

This, the most difficult of all races to win and the most coveted, is not only compelling in its unusual depth for the 120th running, but in the fact that the central characters have endured virtually without mishap.

“You’ve got a plan in mind and you can’t be interrupted,” said Randy Winick, who trains Breeders’ Cup Juvenile and Santa Anita Derby winner Brocco, second choice behind Holy Bull on the early wagering line and the most impressive of the Derby starters during his final days of training for the Derby.

“So much has got to fall into place. And you’ve got to have the horse to do it. If the horse doesn’t cooperate, it’s all out the window. This is a tough enough race to win under the best of circumstances.”

Not far from the barn in which Brocco has been quartered since arriving here more than two weeks ago, trainer Ron McAnally has spent the week tending to the final preparation of Valiant Nature for Saturday’s once-in-a-lifetime assignment. His is the colt who denied Brocco the 2-year-old title last season when he upset the Breeders’ Cup winner in the Hollywood Futurity. And this, McAnally believes, is his best chance to win a Kentucky Derby since 1962. He was derailed at the 11th hour when Donut King, winner of the Champagne Stakes as a 2-year-old, suffered a bruised hind hoof and was scratched.

“First, you’ve got to have a horse with the ability and the capacity to get the distance,” McAnally said. “You’ve got to have a sound horse. And then, there’s luck. No question about that.”

When last they met, in March, Brocco was a head better than Valiant Nature in the San Felipe Stakes at Santa Anita. Both made their initial starts of the new season and were behind upset winner Soul Of The Matter, who will be among the Derby starters Saturday, again in a longshot role with prospects complicated by nagging hoof problems that have interrupted his training.

This time, the test is not between Brocco and Valiant Nature. Holy Bull is favored to overcome his pedigree and 14 opponents. There is support for Go For Gin, Strodes Creek, Blumin Affair, Powis Castle and Southern Rhythm as well as the two best 3-year-olds from California.

“I think (Brocco) is the horse to beat,” Winick said. “It will take an excellent effort to beat this horse. I’ve been fortunate to be able to keep him on schedule. For a race this tough, that’s important. You can’t give anything away. But I feel great about this horse going in. He’s right and he’s ready.”

McAnally has the only horse in the field to have faced both Brocco and Holy Bull, to whom he finished second in the Blue Grass Stakes at Keeneland three weeks ago. Valiant Nature ran the kind of race in the Blue Grass from which he figures to move forward Saturday and McAnally believes he saw a flaw in Holy Bull’s armor that day.

“When (Holy Bull) hit the finish line, he pulled himself up in about three jumps,” McAnally said. “Unless the gray horse is that smart, maybe a mile-and-an-eighth is about as far as he wants to go. (Valiant Nature) galloped past him beyond the wire and must have been 20 lengths in front of him galloping out.”

Valiant Nature’s experience, or lack of it, is McAnally’s main concern. Then, there is the matter of Holy Bull. Winick, a study in confidence, is concerned only that the race develop in a manner that gives Brocco a chance.

“My horse will run his race,” he said. “I just hope someone entertains (Holy Bull) out there. You can’t give anything away.”