The man on the horse is...

Harry Allen Jerkens (born April 21, 1929 in Islip, Long Island, New York), an American Thoroughbred race horse Hall of Fame trainer.

Jerkens' father owned a riding academy on Long Island that led to his interest in horse racing and in 1950 he trained his first winner. Sometimes called the "Giant Killer", he is best known for his upsets, twice having horses that defeated Secretariat and three times his horses beat Kelso. In addition his horses have defeated other greats such as Buckpasser, Riva Ridge, and Forego.

In 1973, H. Allen Jerkens was voted the Eclipse Award for Outstanding Trainer and in 1975 he became the youngest trainer ever inducted into the National Museum of Racing and Hall of Fame at the age of 45. Still active, he has trained more than 160 stakes winners including Duck Dance and Tunex.

His son Jimmy followed in his foosteps and is also a successful trainer.