 As a third baseman, his powerful arm remained an asset, and he remained at that spot for more than 15 years.Brett's minor league stops were with the Billings Mustangs for the Rookie-level Pioneer League in 1971, the San Jose Bees of the Class A California League in 1972, and the Omaha Royals of the Class AAA American Association in 1973, batting .291, .274, and .284, respectively.The Royals promoted Brett to the major leagues on August 2, 1973, when he played in 13 games and was 5 for 40 (.125) at age 20.