At first i thought he might have saw something that hit the track, but on review, it looks like he spooked when he was hit with the whip, which was the first time he was ever hit with a whip in his life apparently.
http://www.bloodhorse.com/horse-racing/ ... z1aORxtOnd
“He’s a really good horse. He’d never been hit (with a crop) in his life. He’s so fast (that) we’ve never even had to lay a stick on him. I think he was shocked. Julien rolled the stick over and hit him right-handed, and the horse was just shocked. That scared him over the rail.
I mean make no mistake I don't profess to be Monty Roberts or antyhing, but i would think that's part of getting a horse ready for the races, no different than schooling a horse, you have to get a horse used to being hit with the whip (I would think). I mean it's not they thought he never was going to have to use the whip on the horse ever.
Sadly this seems like something that could have been easily avoided.