SARATOGA SPRINGS, N.Y. - Adding injury to insult for Team Rachel Alexandra, their top 2-year-old colt, Kantharos, has been retired from racing after suffering fractured sesamoids in his left foreleg following a Monday workout at Saratoga. On Monday, Kantharos worked five furlongs in 1:03.90 over the Oklahoma training track, but apparently took a bad step galloping out. Back at the barn, he appeared to be uncomfortable as he was led around the walking ring. X-rays revealed the injury. Kantharos is owned by Jess Jackson’s Stonestreet Stable and trained by Steve Asmussen, the same connections of Rachel Alexandra, last year’s Horse of the Year. Rachel Alexandra suffered a one-length defeat in Sunday’s Grade 1 Personal Ensign Stakes, her third loss from five starts this year. "This horse is a magnificent athlete," Jackson said of Kantharos in a press release. "We are stunned, shocked and terribly saddened by this awful event. At this same time we are hoping that this injury will heal completely. At this point, his prognosis for a healthy recovery is good, but in any case, his racing career is over." Kantharos, a son of Lion Heart, won his first three starts by a combined 28 1/2 lengths. He won a maiden race at Churchill in May by 11 3/4 lengths, followed by the Grade 3 Bashford Manor by 9 1/2 lengths on July 3. On Aug. 16, he won the Grade 2 Saratoga Special by 7 1/4 lengths at Saratoga. He was nominated to next Monday’s Grade 1 Hopeful. "This was a tragic and unforeseeable event," Asmussen said in a press release. "The brilliance that he had shown was a foretaste of his limitless potential. Right now, we are following his progress closely."