LOUISVILLE, Ky. -- Buddha, the co-second favourite in early betting for the Kentucky Derby, was withdrawn from the race early Friday after coming up lame.

"The horse came out of his stall right before 5 a.m. and he was off in his left front leg," said a visibly upset James Bond, the colt's trainer.

"I always said I wouldn't come to the Derby unless I had a horse that could really run...I thought this horse was going to be the horse."

Pat Day, Churchill Downs' all-time winningest jockey and a Derby winner in 1992, was scheduled to ride the colt, but instead he will now be aboard 30-1 chance Blue Burner.

Corey Nakatani gave up the mount on Blue Burner after taking a spill during a race at Hollywood Park in California on Thursday. Nakatani complained of dizziness and has decided against riding in the Derby.

Buddha's exit reduces the field to 19 runners. He and Came Home were priced at 5-1 in early betting, second only to favourite Harlan's Holiday at 9-2. Medaglia d'Oro and Johannesburg are third choices at 6-1.