Doping in baseball has been an ongoing issue for Major League Baseball (MLB). After repeated use by some of the most successful professional baseball players in MLB history, these banned substances found their way to the collegiate level. At the junior college level, due to lack of funding and NCAA drug testing, the abuse of PEDs is most common, but they are also an issue in Division I, II and III.

Mark David McGwire, nicknamed "Big Mac", is an American former professional baseball first baseman who played 16 seasons in Major League Baseball (MLB) from 1986 to 2001 for the Oakland Athletics and the St. Louis Cardinals. He won two World Series championships, one with Oakland as a player in 1989 and one with St. Louis as a coach in 2011. One of the most prolific home run hitters in baseball history, McGwire hit 583 home runs during his career, which ranked 5th-most in MLB history at the time of his retirement and currently ranks 11th. He holds the major-league career record for at bats per home run ratio (10.6), and is the former record holder for both home runs in a single season and home runs hit by a rookie. McGwire was one of several central figures in baseball's steroids scandal.