LOUISVILLE, Ky. -- Crown of Thorns, a leading contender for Saturday’s $1 million Breeders’ Cup Dirt Mile, was scratched from the race on Friday after he developed a recurrence of an old injury to his right knee. "He had an old knee problem crop up, nothing serious, but he can’t run on it," trainer Richard Mandella said Friday morning. "He’s had his issues through his life; it’s nothing terrible but it’s a problem that cropped up, so we’re out." Mandella said Crown of Thorns did not cool out well following his normal gallop Thursday morning and when the he checked the horse Friday he was still off, "so we’re not going to compromise him," Mandella said. The scratch of Crown of Thorns reduces the field for the Dirt Mile to 12. Mandella said further X-rays would be taken on Crown of Thorns to determine the extent of the injury. Mandella also said he would talk with owner B. Wayne Hughes on Saturday to decide whether to attempt to try and bring him back. "We could still keep going, it’s whether he wants to keep going or not," Mandella said. "We’re going to look at the options, we’re going to get a couple of veterinarians to look at it and see if we can improve our game a little bit." Crown of Thorns, a 5-year-old son of Repent, has had a history of infirmities, but when he was right, he rarely failed to fire. He has only won 2 of 8 starts, but finished second in his last four starts -- all Grade 1 stakes -- including a nose loss in last year’s Breeders’ Cup Sprint and half-length losses in this year’s Pat O’Brien and Goodwood. Mandella said he was very much looking forward to running Crown of Thorns in the Dirt Mile, which is run around one turn. "He was in the form of his life, his works were unbelievable, his races were good," Mandella said. "He’s a very good horse; you could tell the way I approached his races, I never practiced much. He’s just a very good horse -- short or long, no matter what surface it had been on, he was going to be giving them hell."