Jockey Noel Callow has been taken to hospital after a fall at Sandown.
Callow was conscious but complaining of neck and back soreness and suffering concussion after being flung from Vegas Boulevard during the middle stages of the final race.
Stewards have adjourned an inquiry into the fall until Callow is fit enough to give evidence.
Vegas Boulevard was a pick-up ride for Callow who replaced Luke Nolen.
Callow rode the Colin Little-trained Kazio to victory at Sandown.
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