Toby’s Corner (left) and Eddie Castro beat Uncle Mo and John Velazquez in the Wood Memorial. (Bill Kostroun / AP)

Trainer Graham Motion said the horse wasn't 100 percent Monday and was sent for an exam at the New Bolton Center, a Pennsylvania equine hospital.

“After what was a perfect work on Sunday, we weren't 100 percent happy with him yesterday,” Motion told The Steeplechase Times. “He had a lameness in his left hind, we had him looked at here and then we sent him to New Bolton. At this point, there's nothing obvious that's causing the lameness. We had to make a decision as to whether he could get on a van for Kentucky this morning and obviously he couldn't.”

Derby Kitten, winner of the Lexington Stakes, is expected to be added to the field, which is limited to 20. The draw is Wednesday.

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