Trainer Nick Zito said Saturday that X-rays revealed a small fracture in the left front ankle of last year's champion 2-year-old.
"It's unfortunate -- it just wasn't meant to be, maybe," said Zito, a two-time winning Derby trainer. "It's a shame because he has all the ability in the world. He's one of the best I've ever had."
War Pass was unbeaten in four races in his championship campaign and had one win in three starts this year. The colt has earnings of $1.58 million and led all Derby contenders in graded earnings with $1.47 million.
LEXINGTON STAKES: Todd Pletcher has gone from having no Kentucky Derby qualifier to having three in a week. The latest, however, likely won't be joining him at Churchill Downs.
Behindatthebar won the $325,000 Lexington Stakes at Keeneland, picking up $201,500 -- more than enough graded stakes earnings to qualify for next month's Derby.
Although Pletcher didn't rule out a Derby appearance for his colt, he said it was doubtful the horse would join stable mates Monba and Stonerside Stable's Cowboy Cal in the May 3 Run for the Roses. Those two finished first and second in the Blue Grass Stakes a week ago, also on Keeneland's Polytrack.
Besides Behindatthebar, the only horse to run in the Lexington that has sufficient graded stakes earnings to qualify for the Derby was Salute the Sarge. However, the horse finished seventh.