LOS ANGELES — William G. Baffert, the father of Hall of Fame thoroughbred trainer Bob Baffert, died yesterday. He was 88.

The younger Baffert announced his father’s death via Twitter. Nicknamed “The Chief,” Bill Sr. was the mentor for his son as a trainer. He died at his home in the U.S.-Mexico border town of Nogales, Ariz., according to the Daily Racing Form.

No cause was given, although his son said recently that Bill Sr. had been in declining health.

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