ARCADIA, Calif. -- Geaux Rocket Ride was euthanized on Wednesday, four days after getting injured during a workout leading up to the Breeders' Cup and struggling to recover after surgery.
The colt's owner, Pin Oak Stud, posted the news of the death on social media.
It's the second death this week leading up to this weekend's Breeders' Cup at Santa Anita.
Practical Move, a contender in the $1 million Dirt Mile, collapsed on the track after a gallop Tuesday. Breeders' Cup officials said his death was due to "a cardiac event." A required necropsy will determine the official cause.
Geaux Rocket Ride was being pointed toward the $6 million Breeders' Cup Classic when he got hurt. He appeared to stumble and was pulled up by Hall of Fame jockey Mike Smith. He jumped off and held the 3-year-old colt's right front leg until help arrived last Saturday at Santa Anita. Smith wasn't hurt.
Geaux Rocket Ride suffered a condylar fracture. It's a repetitive strain injury that results in a fracture to the cannon bone above the fetlock due to large loads transmitted during high-speed workouts.
Hall of Fame trainer Richard Mandella told The Associated Press via text earlier Wednesday that respected veterinarian Dr. Larry Bramlage was en route to California to look at Geaux Rocket Ride and make an evaluation.
"His mind and his spirit never quit, but his body never recovered from surgery," Pin Oak Stud wrote. "He had a very rare response post-op and he wasn't able to stand up again. He fought hard and our team of vets tried everything they could."
Horses that can't stand are at increased risk for complications such as pressure sores, colic and pneumonia.
Geaux Rocket Ride missed the Santa Anita Derby and this year's Triple Crown races because of a fever and a high white cell count. A few weeks ago, the colt had a temperature that interrupted his training.
But Mandella had said the colt was recovered and back on track toward the Breeders' Cup.
Geaux Rocket Ride won the Haskell in July, beating Kentucky Derby winner Mage, and finished second in the Pacific Classic in September. He has three wins in five career starts and earnings of $980,200.
Pin Oak Stud said it appreciated the support it received from the public.
"We made sure he knew how loved he was," the stable wrote. "We will miss you forever, Rocket."