(1.63 m) and weighed 111 lb (50 kg), a size that enabled him to pursue a career as a jockey in Thoroughbred horse racing.

By his third season of racing, Hartack was the United States' leading jockey in both wins and money earned.

Hartack led the nation in races won four times, and was the first rider to have purse earnings of $3 million in a season.

In 1967, Hartack authored (with Whitney Tower) a three-part series in Sports Illustrated titled "A Hard Ride All The Way."

Winners ridden in Triple Crown Classic races : On November 26, 2007, two weeks before what would have been his 75th birthday, Hartack was found dead from an apparent heart attack in a cabin at a camp near the town of Freer, Texas while on a hunting vacation.