updated 11:54 p.m. ET May 2, 2008

LOUISVILLE, Ky. - Eight Belles has never raced against the boys. The gray filly will get her big chance when she takes on 19 of ’em in the Kentucky Derby.

A trio of horses — Colonel John, Bob Black Jack and Gayego — used to running on Southern California’s newer synthetic tracks will hit the dirt at Churchill Downs on Saturday, making for an interesting mix of 20 3-year-olds going 1¼ miles.

“It’s the Derby,” track oddsmaker Mike Battaglia said Wednesday. “Strange things seem to happen in the Derby.”

Unbeaten in three career starts, Florida Derby winner Big Brown was made the 3-1 favorite after drawing the far outside No. 20 post. Eight Belles drew the No. 5 post and was 8-1 on Friday.

Eight of this year’s 20 horses ran their final pre-Derby races on synthetic surfaces, compared to just two last year. But those two did quite well — Street Sense won and Hard Spun was second.

“The (synthetic surface) is just another X factor to throw in,” Battaglia said. “The synthetic tracks make it very tough (to handicap). Look at Colonel John. He’s never raced on dirt.”

Trained by Eoin Harty, Santa Anita Derby winner Colonel John is 4-for-6 with two runner-up finishes on the synthetic surface made of wax-coated sand, fibers and recycled rubber. He had an exceptionally fast workout at Churchill Downs earlier in the week.

“He seems to move even better on the dirt than he does on the synthetic track,” Harty said. “It’s the only dirt track he’s been on, so that’s the only gauge I have.”

Bob Black Jack got overtaken by Colonel John in the stretch of the Santa Anita Derby and lost by a half-length. The colt has been out of the money once in seven career starts on synthetic surfaces for James Kasparoff, who like Harty is a first-time Derby trainer.

“When you get off synthetic and you get on dirt, these horses seem to fly on it,” Kasparoff said. “You come off synthetic and your fitness level is very, very high.”

The third California horse, Gayego, is 1-0 on dirt after winning the Arkansas Derby by three-quarters of a length. He is 2-for-4 on synthetic surfaces and was never worse than second in his two defeats.

“He’s as good as he can be for this and he’s coming up to it as well as we could have wanted,” said Paulo Lobo, another first-time Derby trainer.

Larry Jones talked with Hall of Famers D. Wayne Lukas and LeRoy Jolley, the last two trainers who won the Derby with a filly. Both of them encouraged Jones to give Eight Belles a shot at the boys.

“The only time Eight Belles has ever beat any boys was when I worked her in the morning with mine,” Jones said, referring to the male horses he trains.

Only three fillies have won the Derby, the last was Winning Colors in 1988. None has run in the race since 1999.

Learn how to rate contending horses, then let computer help you pick winner

“If she runs her race against the colts and doesn’t get intimidated we feel like she can be right there,” said Jones, who finished second last year with Hard Spun.

Big Brown has inexperience to overcome.

The last Derby winner with just three previous career starts was the filly Regret in 1915; and only two winners in the past 60 years have overcome having two 3-year-old preps, Sunny’s Halo in 1983 and Street Sense last year.

“I feel that if we run our race, and he breaks clean, I don’t see a horse as of yet that can beat Big Brown,” trainer Rick Dutrow Jr. said. “I just don’t see it. I don’t want to see it, either.”

The only Derby winner to leave from the No. 20 post was Clyde Van Dusen in 1929.

“We prefer just to break on the outside,” Dutrow said. “We get assured of a clean trip. If he breaks good, we figure it’s to our advantage. We had a few choices and felt we took the best shot.”

Slide show   The Week in Sports Pictures Manny messes up, the Tour takes off to Spain, Nomar returns and more. more photos

Big Brown will be ridden by two-time Derby winner Kent Desormeaux; Derby rookie Gabriel Saez is on Eight Belles, who brings a four-race winning streak into the Run for the Roses.

Pyro is coming off the worst race of his career, a 10th-place finish in the Blue Grass in his only start over a synthetic surface. The colt trained by Steve Asmussen won the Risen Star and the Louisiana Derby in his two previous starts.

Asmussen, who also trains Z Fortune, says he expects Pyro to “run his lifetime best when it matters most.”

Harty has his first Derby horse, although he’s no stranger to what can happen when 20 horses race down the long stretch to the first turn. He was Bob Baffert’s top assistant when the California trainer won in 1997 and 1998.

“It’s a tough race, especially getting in and out of the first turn in one piece,” Harty said. “You can strategize all you want, but when the gates open, it’s every man for himself.”

MORE FROM HORSE RACING

Haskell will pit Preakness winner vs. Belmont winner

Haskell will pit Preakness winner vs. Belmont winner Lawyer Ron, a champion in 2007, is euthanized Pioneerof the Nile retired with leg injury Dutrow suspended 30 days for drug violation   Video: Filly Rachel Alexandra wins Preakness thriller   Watch replay of Mine That Bird's victory Interactive: Triple Crown winners, near misses Vote: When will we see next Triple Crown winner? Equibase: Quick results from top tracks Equibase: Results ticker from top tracks   Add Horse racing headlines to your news reader: