Grindstone retired after Derby victory

Grindstone, who last Saturday won the Kentucky Derby, was yesterday retired to stud after it was discovered that he had chipped a bone in his off-fore leg. The injury was discovered in Grindstone's knee following a morning workout at Churchill Downs, the first workout for the horse since winning the Derby on the same track at the weekend.

Grindstone showed discomfort coming off the track and radiographs revealed the injury, the colt's owner, William Young, reported in a statement. "This is in the best interest of the health of the horse," Young said. "This injury is not life-threatening to Grindstone, it's simply the right thing to do."

The colt, the son of the 1990 Kentucky Derby winner, Unbridled, becomes the first Derby winner to miss the Preakness since Spend A Buck in 1985.

Grindstone, whose career ends with three wins and two seconds in just six starts, had career earnings of $1,224,510. He will stand at Young's Overbrook Farm in Lexington.

Grindstone nosed out Cavonnier in a photo-finish last Saturday to give his trainer, D Wayne Lukas, an unprecedented sixth straight Triple Crown win.

Lukas will still have a chance to extend his streak at the Preakness Stakes in Baltimore on Saturday week. Before the injury to Grindstone, Lukas had planned to enter as many as four horses in the Preakness, including the strong Derby contenders Prince Of Thieves (who finished third) and Editor's Note (sixth).

The absence of Grindstone will weaken a Preakness field that will likely also be without Unbridled's Song, who was fifth in the Derby.