The Kentucky Derby winner finished training feeling sore in the same leg he suffered a slab fracture last year.
Animal Kingdom pulls out of the Dubai World Cup
Animal Kingdom will not be coming to UAE to contest the Dubai World Cup after he suffered an injury in routine track work today.
The Kentucky Derby winner was slated to line-up in the world's richest race at Meydan Racecourse on March 31 after winning his prep race last month.
It was the four year old's first race since he suffered a slab fracture on his near hind leg in the Belmont Stakes last year.
"Sorry to report that AK will not be making the trip to Dubai. He came out of his work sore in the same leg that he injured in the Belmont," Graham Motion, the trainer, said on Twitter yesterday.
"Disappointed for everyone involved, especially the horse. Hope to get him back on track."
A slab fracture occurs when the front part of the bone breaks off the carpal bone in a horse's knee.
Animal Kingdom almost fell to the floor in June when coming out of the gate in the third leg of America's Triple Crown series.
Motion noticed signs of lameness in work after the race but an X-ray showed the extent of the injury.
Animal Kingdom was given the summer off, missing the lucrative Breeders' Cup meeting, and started training again for Dubai's US$10 million (Dh36.7m) contest in December.
He warmed up for his task with a facile win in a conditions race at Gulfstream Park, winning with a blitz of speed in the final quarter of a mile to suggest he had fully recovered.
Trained in Maryland on Motion's Tapeta surface, he was a leading candidate for the Dubai World Cup and after Capponi burst some big reputations in the third round of the Maktoum Challenge at Meydan on Saturday he was considered one of the most likely winners.