Grade 3 Sham Stakes hero Out of Bounds, who fired a bullet work at Hollywood Park on Monday, exited the impressive move with an injury that has knocked him off the Triple Crown trail, Daily Racing Form reports.
"He worked fantastic," Harty told DRF, "but we noticed something wrong as he was cooling out."
Out of Bounds sustained a non-displaced condylar fracture to his left front ankle. The Discreet Cat colt will undergo surgery, forcing him onto the sidelines for the forseeable future. With sufficient recovery time, he is expected to be able to resume racing.
Out of Bounds had drilled five furlongs in :59 1/5, best of 23 at the distance on the Cushion Track.
Monday's work was designed as his final major tune-up for Saturday's Grade 2 San Felipe at Santa Anita, where he would have been one of the top choices.