Donald "Donnie" Andrew Miller Jr. (born June 11, 1963) is a retired thoroughbred horse racing jockey who competed from the 1980s to mid 1990s. Miller started racing in the early 1980s and had the most wins as an apprentice jockey in 1981. As a jockey, Miller won twenty three graded stakes races from 1982 to 1992. Of his wins, Miller won the 1983 Preakness Stakes with Deputed Testamony as part of the Triple Crown of Thoroughbred Racing.