DEL MAR, Calif. – A workout for Kentucky Derby contender Authentic had to be aborted shortly after it began early Monday morning at Del Mar owing to a catastrophic ankle injury suffered by another horse working about five furlongs in front of him, which caused warning sirens to go off and the track’s outriders to instruct all riders to immediately pull up their horses. Bob Baffert, the trainer of Authentic, was watching the work from the grandstand and was in radio contact with exercise rider Juan Ochoa, who was aboard Authentic. “Pull up,” Baffert said to Ochoa as soon as he saw what was unfolding near the finish line. Authentic, who had broken off before the five-furlong pole, was about an eighth of a mile into his work and took about another eighth to be brought safely to a stop. Authentic was taken back to the barn while an equine ambulance was brought out to transport the injured horse, who was near the finish line. :: Play the Kentucky Derby with DRF! Visit our Kentucky Derby shop for Packages, PPs, Betting Strategies, and more Rather than bring Authentic out anew later in the morning, Baffert decided the best approach was to simply postpone the work for 24 hours, until Tuesday. This work, the penultimate one for Authentic in advance of the Kentucky Derby on Sept. 5, was to be far more serious than his final work, scheduled for Sunday. Baffert had scheduled six days between those works, but now it will only be a five-day gap. Authentic is scheduled to fly to Kentucky next Monday, Aug. 31, so for the final work to take place here, it has to be Sunday. Authentic is coming off a victory in the Haskell, which followed his lone career loss, a second-place finish to Honor A. P. in the Santa Anita Derby. :: KENTUCKY DERBY 2020: Derby Watch, point standings, prep schedule, news, and more Track officials identified the stricken horse as Irreproachable, a 4-year-old gelding trained by Phil D’Amato who had raced twice, most recently finishing second in a maiden-claiming race July 24 at Del Mar. He is the second horse catastrophically injured in a work this summer at Del Mar, which opened for training nearly two months ago. There have been no catastrophic injuries in any races this summer, nor were there any during the summer meet of 2019. Also Monday, the 2-year-old Dr. Schivel, a recent maiden winner and a top contender for the Grade 1 Runhappy Del Mar Futurity on closing day, Sept. 7, worked a half-mile in 48.60 seconds for trainer Luis Mendez.