KENTUCKY DERBY : Probable Favorite Has Flaws : Horse racing: The gelding Prairie Bayou goes against the grain of most past winners, but he has been a success.

Prairie Bayou will have four strikes against him today when he tries to beat 18 other 3-year-olds in a Kentucky Derby that has boiled down to not being as wide-open as previously advertised.

Strike 1: Prairie Bayou, listed at 5-2 on the morning line, will be a moderate favorite at post time and must carry the historical baggage of 13 consecutive defeats for Derby favorites. The last public choice to win at Churchill Downs was Spectacular Bid in 1979.

Strike 2: Prairie Bayou is a gelding. Only seven geldings have won the 118 previous runnings of the Derby, the last Clyde Van Dusen in 1929.

Strike 3: The gurus of dosage, that arcane mathematical pedigree formula that is supposed to be Derby gospel, say that Prairie Bayou is beyond their prescribed thresholds. Strike The Gold defied the dosage experts when he won the Derby two years ago.

Strike 4: Prairie Bayou runs from far off the pace, a risky style in an unwieldy field.

Of the four negatives, the fourth is the most significant. Prairie Bayou’s wide, sweeping moves, so successful in the Jim Beam Stakes at Turfway Park and the Blue Grass at Keeneland in his most recent Derby preps, are frequently the undoing of good horses in the Derby. This year’s likely Derby scenario is that front-runners Storm Tower and Personal Hope will ensure an honest pace, and with the leaders backing up through the 1,234 1/2-foot stretch, a late-running horse should win. Prairie Bayou is expected to be one of the closers.

In such a projection, a trainer would probably prefer to have a Union City, who will be much closer to the pace, or a Bull Inthe Heather, who will come from the middle of the pack, but Tom Bohannan, Prairie Bayou’s conditioner, is not apologizing for his position.

“We worked Prairie Bayou about five days before the Blue Grass and let him pick it up in the eighth of a mile, and that worked,” Bohannan said. “We did the same thing here, and we hope it’s still the right thing.”

Prairie Bayou’s post position, the weather and his coolness under fire are all positives. “No. 5 (post) is ideal,” Bohannan said. “It wouldn’t have mattered even if he had drawn something like the 12. The horse doesn’t do much early racing. He doesn’t have to be strategically placed in the gate.”

The forecast is for mostly cloudy skies, temperatures in the high 70s and a 30% chance of thundershowers not likely to reach Churchill Downs until after the Derby has been run.

Many Derby horses are nervous wrecks by the time they reach the gate, but Bohannan doesn’t expect Prairie Bayou to behave any differently than he has in other races. “He’s a very calm and passive horse,” the trainer said. “He doesn’t get excited over much. He’s got the kind of temperament you like to have in a horse, especially when you have to lead him over in front of 130,000 people.”

Prairie Bayou might have the best chance for a Derby victory by a gelding since Best Pal finished second in 1991. The gelding Rockhill Native went off as the 2-1 favorite in 1980 and ran fifth as Genuine Risk, a filly, won the race. Rockhill Native started the streak of losing favorites. The others: Proud Appeal, Air Forbes Won, Marfa, the entry of Life’s Magic and Althea, Chief’s Crown, Snow Chief, Demons Begone, Private Terms, Easy Goer, Mister Frisky, Hansel and Arazi.

“The horse doesn’t know whether he’s favored or not,” Bohannan said. “That’s the least of my considerations.”

The Field

* TV: Channel 7, 1:30. * Post: 2:38 p.m. PDT

No. Horse Jockey Odds 1. Storm Tower Wilson 9-2 2. Kissin Kris Santos 30-1 3. f-Truth Of It All Velasquez 8-1 4. Union City Valenzuela 8-1 5. Prairie Bayou Smith 5-2 6. Sea Hero Bailey 30-1 7. Personal Hope Stevens 7-2 8. Rockamundo Borel 20-1 9. f-Silver Of Silver Vasquez 8-1 10. Bull Inthe Heather Ramos 10-1 11. f-Tossofthecoin Pincay 8-1 12. f-Mi Cielo Gryder 8-1 13. f-Wild Gale Sellers 8-1 14. f-Ragtime Rebel Lester 8-1 15. Dixieland Heat Romero 15-1 16. Wallenda Day 15-1 17. a-Corby McCarron 12-1 18. a-Diazo Desormeaux 12-1 19. f-El Bakan Perret 8-1

a-Allen Paulsen owned entry. f-mutuel field.

Fastest Times

Fastest times by winners of the 1 1/4-mile Kentucky Derby:

Horse Year Time Secretariat 1973 1:592/5 Northern Dancer 1964 2:00 Spend A Buck 1985 2:001/5 Decidedly 1962 2:002/5 Proud Clarion 1967 2:003/5 Lucky Debonair 1965 2:011/5 Affirmed 1978 2:011/5 Whirlaway 1941 2:012/5 Middleground 1950 2:013/5 Hill Gail 1952 2:013/5 Bold Forbes 1976 2:013/5 Twenty Grand 1931 2:014/5 Swaps 1955 2:014/5 Chateaugay 1963 2:014/5 Majestic Prince 1969 2:014/5 Riva Ridge 1972 2:014/5