Casino Drive, with Edgar Prado up, gallops around the track during a training run Thursday, June 5,... 
(AP Photo/Julie Jacobson)
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Big Brown's biggest obstacle to the first Triple Crown in three decades pulled out of the Belmont Stakes this morning.
Casino Drive, the horse handicapped as having best chance to crush odds-on favorite Big Brown's Triple Crown dreams, was scratched from the race because of a bruised left hind hoof.
Casino Drive had a light workout early this morning, but began to favor the hoof during a post-jog bath, the horse's racing manager Nobutaka Tada confirmed. While only a minor injury, the decision to shelf the Japanese race horse was taken as a precationary measure.
The exit takes Big Brown a step closer to capturing horse racing's most prestigious prize, the Triple Crown, a sporting feat not accomplished since 1978 when Affirmed made racing history.
Big Brown, who won both the Kentucky Derby and Preakness with relative ease, is the runaway favorite in today's Belmont Stakes, which goes off a 6 p.m. in Elmont, N.Y. The horse's owner, Michael Ivarone, and jockey, Kent Desormeaux, both hail from Long Island, N.Y.
"I expect him to win it," Iavarone told ABC News. "I think it's his destiny."
Only eleven other horses have ever won the Triple Crown and the last was claimed decades ago in 1978. The last Triple Crown attempt was in 2004, but the horse, Smarty Jones, was beaten in the final moments of the Belmont's mile-and-a-half course.
"I haven't seen anything like Big Brown," said trainer Rick Drutrow. "And the more that we see of him, the more amazing it seems."
Odds makers were sent scrambling with the news of Casino Drive's scratch this morning. The already large stakes on a Big Brown win were initially upped to one-to-two odds, but dropped slightly to two-to-five, according to the New York Racing Association.
Some have been concerned about an injury to Big Brown this week -- small crack in a left hoof. But there is nothing to worry about, according to Big Brown's veterinarian.
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