>>catherine callaway is live with a veterinarian who has seen this before.e is this injury? certain bad for i'll have another. >> reporter: joining me is megan, a veterinarian. come over here. we're going to talk about that injury. believe it or not, this thoroughbred racing horse has the same issue, tendinitis. more severe than what i'll have another has. megan, you have to wonder with such a mild case of i'll have another, why did they pull him from the race? >> the type of injury i'll have another has is mild. he's not lame. potentially, he could race on it, but for a horse at the top of his game, he's just won the derby, the preakness. it is more advantageous for them to retire him as a champion and let him go stud than to risk potentially worsening his injury or worse case, ending catastrophic. >> the racing horse that has tendinitis. this is a normal tendon and this is a bowed tendon which could have happened if i'll have another had pulled it. talk a little about what that trainer said. called it a freakish injury. he said he means it's unexpected. no