Alydar's well known rivalry with Triple Crown winner Affirmed began when the colts were 2-year-olds. That rivalry continued the following year when Alydar was narrowly defeated in each of the Triple Crown races. In fact, he was the first horse to run second in all three races.
At 2, Alydar won the Sapling, but the highlight of this year was his victory over Affirmed in the Grade 1 Champagne Stakes. Despite running second in each of the Triple Crown races, Alydar's 3-year-old season was his best. He won the Florida Derby, Flamingo Stakes, Blue Grass Stakes, Arlington Classic, Whitney and Travers (following Affirmed's disqualification).
At 4 Alydar won the Nassau County Handicap but retired later in the season after an injury.
Alydar was the sire of 10 champions who won over $24 million. His first classic winners were Alysheba, 1987 Derby and Preakness winner, and Easy Goer, winner of the 1989 Belmont.
Alydar was inducted into the Hall of Fame in 1989.