LOUISVILLE, Ky. -- No one knows Big Brown better than Michelle Nevin.

The exercise rider for the unbeaten Kentucky Derby favorite has ridden the big bay colt more than 100 times, and she remains awed by his graceful stride and powerful running style.

"The horse just floats over the ground," Nevin said in her Irish brogue after Big Brown's final workout before the Derby tomorrow. "You don't feel like you're going that fast at all. He just lengthens his stride. It's very smooth. It's very comfortable. He's like a powerhouse underneath you."

Big Brown, the colt with three victories by a combined 29 lengths, has created quite a backstretch buzz at Churchill Downs.

Dozens of photographers followed Big Brown to the track for yesterday's tuneup. Fans gawked at the striking colt, with one hollering, "There goes the Derby winner."

After breezing three furlongs in 35.40 seconds, Big Brown barely worked up a sweat and walked back to the barn with a bounce in his step.

Asked if she was concerned about any of the 19 other horses in the field, Nevin smiled.

"Not after that," she said.

Big Brown has overcome tender front feet to take all involved on quite a ride. Trainer Rick Dutrow Jr. is telling everyone he has the best horse and plans to bet as much money as he can on Big Brown to win. Jockey Kent Desormeaux is as confident of victory as Dutrow. And IEAH Stables was so taken with the colt after his first victory, it paid a reported $3 million to own a 75 percent share.

The horse is named for UPS, a client of minority owner Paul Pompa Jr., and that has generated additional interest. During Dutrow's news conference, a UPS man dressed head-to-toe in brown wheeled up a bale of hay and made a mock presentation. The shipping label read: "To Big Brown, Kentucky Derby winner's circle."

Big Brown will have to deliver from the outside No. 20 post, where only one other Derby winner started from (Clyde Van Dusen in 1929).

"We're not worried," Dutrow said.

"His talent and his ability got us here, not my training technique. Any good enough horseman can do what I've done with this horse. Any jockey can do what Kent has done with this horse. Any groom, any hotwalker. It's the horse making the whole game go."

The game started slowly for Big Brown, who missed training for two long periods with quarter cracks, the first cracked hoof on the left front foot, the second on the right front foot.

Big Brown won his career opener Sept. 3 at Saratoga by 11 1/4 lengths. A few days later, Pompa had numerous offers for the colt. The most appealing came from IEAH, which allowed Pompa to retain an interest in the colt.

"I watched it on TV and called Rick at his house in Saratoga and told him I have to own that horse," IEAH co-president Michael Iavarone said.

Dutrow watched a race replay and returned the call. "I can find a stall for him," he said.

Big Brown missed 45 days while an abscess from the crack healed. In mid-December at Palm Meadows in Boynton Beach, Fla., the second one appeared and Big Brown did not go to the track in January.

Ian McKinlay, a hoof specialist from New York, fitted Big Brown with special rubber-tipped, glue-on shoes at $550 a pair.

"When he hits the ground, it takes some of that concussion away," Dutrow explained.

Since then, with Desormeaux astride for the first time, Big Brown won an allowance race March 5 at Gulfstream Park by 12 3/4 lengths, and 24 days later rolled to a five-length win in the Florida Derby.

Three races, three wins. The only unbeaten horse in the Derby.

Three-time Derby winner jockey Gary Stevens has been watching the contenders at Churchill Downs for 11 days now. He has seen them all, and Big Brown is like no other.

"It's like if you were in the fifth-grade playground," he said, "and you were going to have a pickup game and Shaquille O'Neal came in and said, 'I'm playing with you guys.' "