Clemens was one of the most accomplished pitchers in baseball history when he was accused of doping. Clemens won seven Cy Young awards, an American League MVP award, and two World Series titles, but all of that was called into question after Canseco's 2005 book accused him of using amphetamines, anabolic steroids, and human growth hormone during his career, though he was never suspended from the game. He was also named in the 2007 Mitchell Report, although he has consistently and unconditionally denied the allegations that he used steroids, including in testimony to a Congressional committee in 2008. Clemens was later indicted on perjury charges in 2010 and tried in court, but was found not guilty of perjury in 2012. Clemens has claimed that hard work helped him dominate the majors into the latter stages of his career, and not .
The early years of the NL were tumultuous, with threats from rival leagues and a rebellion by players against the hated "reserve clause", which restricted the free movement of players between clubs. Competitor leagues formed regularly and also disbanded regularly. The most successful was the American Association (1882–1891), sometimes called the "beer and whiskey league" for its tolerance of the sale of alcoholic beverages to spectators. For several years, the NL and American Association champions met in a postseason championship series—the first attempt at a World Series . The two leagues merged in 1892 as a single 12-team NL, but the NL dropped four teams after the 1899 season. This led to the formation of the American League in 1901 under AL president Ban Johnson , and the resulting bidding war for players led to widespread contract-breaking and legal disputes.
When news first broke regarding the Biogenesis clinic documents detailing the list of clients who were being provided illegal supplements, reports suggested players from Major League Baseball, National Football League and National Basketball Association were involved. As the news evolved over time, it was found that only MLB and minor league baseball players were implicated in the scandal. This could partly be attributed to the fact that MLB has the most advanced drug testing available for performance enhancing drugs compared to the NFL and NBA, whose testing lags in comparison.