<P> The National Basketball Association was established in 1949 by merger of the Basketball Association of America (BAA) and National Basketball League but it recognizes the three BAA seasons as part of its own history . In all of its three years the BAA champion was finally determined in a best - of - seven series but its first two tournaments, the 1947 and 1948 BAA Playoffs, were otherwise quite different from the third, which 21st - century NBA playoffs nearly match . In 1947 and 1948, the Eastern and Western Division champions were matched in a best - of - seven series following the regular season, whose winner advanced to the championship round . Meanwhile, four runners - up played best - of - three series to determine the other finalist: the two second - place teams were matched in one short series and the two third - place teams in another; the winners of those two series played another one . In 1947 the Philadelphia Warriors won the runners - up bracket and beat the Western champion Chicago Stags four games to one, which the NBA recognizes as its first championship; in 1948 Baltimore won the runners - up and beat Eastern champion Philadelphia in the final . Both tournaments generated one finalist from the Eastern and one from the Western Division, but only by chance . </P> <P> In 1949 the third and last BAA tournament matched Eastern teams exclusively and Western teams exclusively, necessarily generating Eastern and Western playoff champions to meet in the final . At the same time, the number of playoff teams was increased from three to four from each Division; two rounds of best - of - three series were played, followed by a best - of - seven championship . The main idea was retained by the NBA . Even the 1950 tournament, following a transitional season with three divisions rather than two, initially determined one playoff champion from each division . The Central champion Minneapolis Lakers became the first league champion under the NBA name by defeating Anderson from the West in a best - of - three, with Syracuse from the East idle, and then knocking off the Syracuse Nationals in six games . </P> <P> The 1951 through 1953 playoffs changed the division finals into a best - of - five playoff . With only nine league members in 1953--54, the NBA cut its postseason tournament field from eight teams to six (from 1954 through 1966, the period of eight to nine league members). Round robins were played in 1954, uniquely in NBA history--a three - team round robin among the three playoff teams in each division . From 1955 to 1966, the first - place team in each division was idle while its two runners - up faced played a best - of - three . Division finals were expanded to best - of - seven in 1958 and division semifinals to best - of - five in 1961 . </P> <P> With ten league members again for the 1966--67 season, eight teams were again admitted to the tournament, providing a simple three - round knockout (8 - team bracket). A year later, the division semifinals were changed to best - of - seven playoff . Then, in 1975 and 1977, respectively, a fifth and sixth team were added to each Division, necessitating an additional first round of best - of - three series . </P>

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