Gabriel rode Eight Belles in the 2008 Kentucky Derby and came under sharp criticism when Eight Belles was euthanized after she'd crossed the finish line, a very game second to Big Brown. In cool-down, she collapsed due to fractures in both front ankles. In a letter to the Kentucky Racing Authority, PETA claimed that the horse was "doubtlessly" injured during the race, and therefore Saez bore some responsibility for the injury and euthanization.
Eight Belles' trainer, Larry Jones, has vigorously defended Saez, saying "We have photographs 50 to 70 yards from where this happened and the horse had her ears up . . . If this horse had anything going on with her at the time, she didn't know it. If the horse never had a clue, there's no way the jockey could have had a clue."
The Kentucky Horse Racing Authority did not find any evidence of wrongdoing by Saez.
The day before the Kentucky Derby, Saez rode Proud Spell to a win in the Kentucky Oaks.