When Hall of Fame rider Pat Day charged between Ibn Bey and Thirty Six Red to win the Breeders' Cup Classic at Belmont Park, it capped a magical year for Unbridled. His gutsy victory secured the Eclipse Award for champion three year old colt, and launched Unbridled into a stellar career at stud. The race also cemented Eclipse honors for trainer Carl Nafzger, voted the leading trainer in 1990. It was Nafzger's first Breeders' Cup victory. For Day, it was the second of four Classic wins.
Unbridled won the Kentucky Derby earlier in the year, providing one of the most memorable moments in horse racing history when trainer Nafzger called the stretch run for owner Frances A. Genter, whose failing eyesight made it difficult for her to see the race. He closed out his career with a third place finish in the 1991 Classic. Unbridled retired with eight wins from 24 starts, and earnings of $4,489,475.