Under trainer Fred H. Loschke, at age two Glorious Song won her only start. Texas businessman Nelson Bunker Hunt then purchased a half-interest in her in 1981. In 1979, the three-year-old filly won five significant stakes races at Woodbine Racetrack, and the following year she was never out of the money in her eleven starts. The dominant horse in Canada and the top racing mare in the United States, in 1980 she won races that included the first of two consecutive Dominion Day Stakes at Woodbine Racetrack. Then, under new trainer Gerry Belanger in 1979/80, she raced in the United States, where her coast-to-coast wins included the Top Flight Handicap at New York's Aqueduct Racetrack, the Michigan Mile And One-Eighth Handicap at Detroit Racecourse, and the La Canada Stakes and Santa Margarita Handicap at California's Santa Anita Park.