Double-A (or Class AA) is the second highest level of play in Minor League Baseball (MiLB) in the United States after Triple-A. There are thirty Double-A teams in three leagues at this classification: Eastern League, Texas League, and Southern League. The modern Double-A classification was created in 1946 with the renaming of Class A1, which then contained the Texas League and the Southern Association. After the Southern Association disbanded in 1961, the Eastern League and the original South Atlantic "Sally" League were bumped up to Double-A in the 1963 minor league reorganization. The Sally League changed its name to the Southern League in 1964. As part of the 2021 Minor League Baseball reorganization, the Texas, Eastern, and Southern leagues were replaced by the Double-A Central, Northeast, and South, respectively.
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