Leading Kentucky Derby contender Nadal has been retired after suffering an injury during a piece of work at Santa Anita on Thursday, according to reports in America.

A son of Blame, the unbeaten Bob Baffert-trained colt had last been seen winning his division of the $500,000 Arkansas Derby at Oaklawn Park earlier this month.

He was being aimed towards next month’s Belmont Stakes and had been vying for Derby favouritism with Tiz The Law, but will now head for a stallion career.

Co-owner George Bolton told Bloodhorse.com: “It requires two screws. He is now going to become a stallion. It’s very sad, obviously. I just got the call this morning. It’s a call you never want to get in horse racing.”

The news capped a bad week for Baffert after news was leaked two days ago that his three-year-old colt Charlatan, winner of the other Arkansas Derby division, faces disqualification after testing postive for a prohibited substance.

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