Buckpasser had two trainers, both since inducted into the
U.S. Racing Hall of Fame.
Bill Winfrey began his training, and when he retired,
Eddie Neloy took over and prepared Buckpasser for his three-year-old season. Buckpasser's first race start was on May 13, 1965, in which he ran a poor fourth. It was the only time he did not place. When Buckpasser ran in the
Flamingo Stakes, the race was declared a nonwagering event, forever after being called the "Chicken" Flamingo. After his two-year-old season and spring, he was placed at the top of the Experimental Free Handicap with 126 pounds. Buckpasser developed a quarter crack that kept him out of the 1966
Kentucky Derby, as well as the
Preakness and Belmont Stakes. It took almost three months for the crack to heal. In
Chicago's
Arlington Classic,
Kauai King ran against the strenuous protests of his trainer. He broke down and was retired, while Buckpasser won the race, setting a new world record for a mile with a time of 1:32 3/5. This record stood for two years until
Dr. Fager broke it in 1968, running 1:32 1/5. In 1989, Buckpasser's grandson, Hall of Fame Champion
Easy Goer, ran a mile in 1:32 2/5. Buckpasser won 15 consecutive races that included the
American Derby (breaking the track record), the Chicago Stakes, the Brooklyn Derby, the
Woodward Stakes, the
Travers Stakes, the
Malibu Stakes, the
Brooklyn Handicap, the
Lawrence Realization Stakes, and the two-mile-long
Jockey Club Gold Cup. With 13 victories as a three-year-old, Buckpasser became the first horse to earn more than $1 million before the age of four. He was named the 1966
American Horse of the Year. His four-year-old season commenced with a win in the San Fernando Stakes. Another quarter crack developed in Buckpasser’s off (right) fore hoof, and he did not race for 4½ months. When he returned, he scored his 15th consecutive victory in the Metropolitan Mile. On June 17, 1967, Buckpasser's winning streak ended with his first and only attempt at racing on grass. He finished third to stablemate Poker in the
Bowling Green Handicap at
Aqueduct Racetrack.
Assagai, the 1966 turf-course champion, finished second. As
The Blood-Horse said in its July 24, 1967, issue: "Never had so many people had so many immunization shots in order to stay home and watch the
Suburban Handicap on Independence Day." Three reasons were advanced for his defeat: turf, shoes, and weight. Buckpasser also ran that day with his head held in an uncommon way, slightly sideways. No one has ever understood why. He won 25 of his 31 races, including a 15-race winning streak, earned five
Eclipse Awards between 1965 and 1967, and was inducted to the
Horse Racing Hall of Fame in 1970. ==Stud record==