Yum! Brands' offer to pay $1 million to the winner of the Kentucky Derby if it beats Barbaro's 6½-length winning margin drew lukewarm reactions yesterday from previous victors.

Derby-winning horsemen agreed that it was unlikely any rider would push a runner just to get a piece of the bonus, which would be split evenly among the owner, jockey, trainer and NTRA Charities Barbaro Memorial Fund.

The bonus is "a great gesture, but if I was the rider of the winning horse in the Kentucky Derby and I came to the last sixteenth of a mile with horse in hand, knowing I was going to win anyway, I would be thinking of the Preakness (Stakes) and the Triple Crown, not about a million-dollar bonus," said jockey Gary Stevens, a three-time Derby winner.

Yum, the Louisville-based parent of KFC, Taco Bell, Pizza Hut and other fast-food chains, joined with Churchill Downs yesterday to announce the bonus. Playing on types of bets like the superfecta and perfecta, the company is calling the bonus the "Yumfecta."

The 61/2-length margin between Barbaro and second-place finisher Bluegrass Cat last year was the second-largest margin in 132 runnings of the Derby. Four horses have won by 8 lengths.

The Derby record-holders are Old Rosebud in 1914, Johnstown in 1939, 1941 Triple Crown winner Whirlaway and 1946 Triple Crown winner Assault.

Yum Chief Executive David Novak said Barbaro's convincing win was "one of the most exciting sports events that I've ever seen."

Novak said the company was pleased with the visibility from last year's Derby sponsorship -- the first in a five-year deal -- but wanted to do something more.

He said the sponsorship is aimed at raising the profile of its corporate identity, compared with its better-known restaurant brands.

The bonus is "certainly creative," said Bob Evans, Churchill Downs Inc. CEO. "It's certainly fun. It has something for the horsemen, which I think is something we always want to embrace. It has the charitable dimension" and prompts people to remember Barbaro.

The horse was euthanized earlier this year because of complications after suffering a broken leg in the Preakness.

Novak said Yum obtained an insurance policy on the payout and will explore the possibility of continuing it if it goes over well.

Unlike an earlier racing bonus by other sponsors that offered $5 million if a horse could win all three legs of the Triple Crown -- the Derby, Preakness and Belmont Stakes -- the Yum challenge deals only with the Derby.

That $5 million Triple Crown bonus was offered between 1987 and 2005, initially under a Chrysler sponsorship and then under Visa. The bonus was never paid; the last Triple Crown winner was Affirmed in 1978.

Evans and Novak said they aren't worried that a trainer or jockey would abuse a horse to get the bonus.

"The rule is you ride hard to the finish," Evans said. "That's the way the game works. And I can't imagine, given the residual breeding values of whoever wins the Derby, that somebody's gonna abuse a horse down there. I just can't believe that's going to possibly happen."

Novak said, "I think that's the least of our concerns, because I think it's everybody's dream to win the Kentucky Derby, and this'll only be an added incentive."

John Servis, trainer of 2004 Derby-winner Smarty Jones, said, however, that he doesn't believe that the bonus is "very good" from a trainer's standpoint.

"I can think of a whole lot better reasons for a bonus, I can tell you that," he said in a telephone interview, echoing Stevens' reasoning.

"From a trainer's standpoint I sure wouldn't be shooting for the bonus," he said.

Derby-winning trainer Carl Nafzger -- the conditioner of last year's 2-year-old champion and Street Sense, one of this year's favorites -- said the bonus is a good public relations deal, but he doesn't think it will cause riders to push horses unnecessarily.

"When you're riding that race nobody's gonna be, 'Oh boy, if I beat on him now and get the (margin).' No … all these jocks are going to want to do is win. When you get to this point you're thinking if you're going to win the Derby, you're already thinking of the next one."

But "if you've got a horse that pulls away, that's good," Nafzger said.

Street Sense did just that last fall at Churchill Downs in winning the Breeders' Cup Juvenile by 10 lengths.