LOUISVILLE, Ky. (AP) -- Long shot Black Onyx is a late scratch for the Kentucky Derby, leaving 19 horses to vie for the roses.

The scratch occurred Friday after early wagering for the race was opened, so Black Onyx's No. 1 post position will be left empty on Saturday. The remaining horses will stay in their original starting gate positions.

The scratch came too late for Fear the Kitten to get into the Derby. The colt was on the list of also eligibles as the 21st qualifier in the point standings which determine the field.

Trainer Kelly Breen gave no immediate explanation for Black Onyx's scratch. It leaves jockey Joe Bravo without a Derby mount.

The 3-year-old colt is 2 for 2 since Breen took over the training last winter. Black Onyx qualified for the Derby by winning the Spiral Stakes at Turfway Park. He was 50-1 on the morning line.

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