Rule 4 draft

The first-year player draft, also known as the Rule 4 draft, is Major League Baseball's primary mechanism for assigning amateur baseball players, from high schools, colleges, and other amateur baseball clubs, to its teams. The draft order is determined based on the previous season's standings, with the team possessing the worst record receiving the first pick. In addition, teams which lost free agents in the previous off-season may be awarded "compensatory" picks.

The first amateur draft was held in 1965. Unlike most sports drafts, the first-year player draft is held mid-season, in June. Another distinguishing feature of this draft in comparison with those of other North American major professional sports leagues is its sheer size: under the current collective bargaining agreement the draft lasts 40 rounds, plus compensatory picks. In contrast, the NFL draft lasts for seven rounds (a maximum of 256 selections), the NHL entry draft lasts seven rounds and roughly 215 picks, and the NBA draft lasts for only two rounds (60 selections).

Major League Baseball has used a draft to assign minor league players to teams since 1921. In 1936, the National Football League held the first amateur draft in professional sports. A decade later, the National Basketball Association instituted a similar method of player distribution. However, the player draft was controversial. Congressman Emanuel Celler questioned the legality of drafts during a series of hearings on the business practice of professional sports leagues in the 1950s. Successful clubs saw the draft as anti-competitive. Yankees executive Johnny Johnson equated it with communism. At the same time, Pulitzer Prize-winning sports columnist Arthur Daley compared the system to a "slave market."

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