LOUISVILLE, Ky. — Flexibility is key in the Kentucky Derby, where 20 horses and riders scramble for position in the early going before the real racing begins late.

"It's a very tough race to ride," said Alex Solis, who will be aboard 3-1 morning line favorite Brother Derek on Saturday. "Instead of having Plan A, B and C, you have to have the rest of it — D, E, F, G."

Solis should know. He's trying to end an 0-for-14 streak in the world's most famous race.

Also looking to break through in his first Derby is Brother Derek's trainer Dan Hendricks, who scoots around in a motorized wheelchair after being paralyzed from the waist down in a motocross accident two years ago.

"He was the main inspiration when I was going through a tough time," Hendricks said. "I thought he was going to become a good horse."

He did, winning all three of his races this year.

Brother Derek's strongest competition includes Lawyer Ron, winner of six in a row, unbeaten Barbaro and a trio of horses trained by Bob Baffert — Bob and John, Point Determined and Sinister Minister.

Baffert, whose cell phone ring tone is "My Old Kentucky Home," seeks his fourth Derby victory.

"I've gone in there with stronger hands and not won," he said. "With 20 horses, there's so much luck involved. You just can't walk up there and say, 'I got 'em."'

The 132nd Derby is wide-open a year after 50-1 long shot Giacomo stunned the Churchill Downs crowd with a late-charging victory.

John Shirreffs, who trains Giacomo, tries again this time with A.P. Warrior. "Give me some wood to touch," he said. "I always need a bit of that."

Another winning trainer is back, too.

Barclay Tagg, the 2003 victor with Funny Cide, brings Showing Up, unraced last year and 3-for-3 this year.

"It takes a lot of luck," he said.

Barbaro and Showing Up are both owned by Gretchen and Roy Jackson's Lael Stable in Pennsylvania. They will be the first owners sending out two unbeaten horses in the same Derby. Smarty Jones in 2004 was the last undefeated Derby winner.

"We all have the same worry," Barbaro's trainer Michael Matz said. "Nobody knows how they're going to react in a 20-horse field."

There's plenty of speed in the race — Sinister Minister, Sharp Humor and Keyed Entry love the lead and should be at the front in the opening quarter mile.

"Hopefully, you get a good start out of the gate and hopefully you don't get tangled up with a bunch of horses that get in your way," Solis said. "The quarter-mile will tell you a lot. You have an idea of what's going to happen, and have a sense of pace and who you're going to follow."

The serious racing, Solis says, begins at the three-eighths pole in the 1Z\v-mile Derby.

"Always you see two, three, four guys that panic and they make those premature moves," he said.

The top three favorites — Brother Derek, Barbaro and Lawyer Ron — all have similar styles, preferring to run on or just off the lead.

But with 20 horses, the field could be strung out in bunches. A.P. Warrior, Jazil and Steppenwolfer might be lurking in the back, waiting to close with a rush.

"It's karma from here on," Baffert said. "We'll see who's been living right, and I've got a big edge there."

Post time is 6:04 p.m. EDT. The forecast calls for partly sunny skies, temperatures in the 60s and a 10 percent chance of rain.