On the death of his father Stephen in 1913, John Sanford inherited Hurricana Stock Farm. His father had been successful in racing and John Sanford would become a major figure in the industry. He raced a number of top horses and in 1916 won the Kentucky Derby with his colt, George Smith. In 1923 he became the first American to win the most prestigious steeplechase race in the world when his horse Sergeant Murphy won the English Grand National. In 1923, Sanford won the American Grand National with Best Play.