Double-A (officially Class AA) is the second-highest level of play in Minor League Baseball in the United States since 1946, below only Triple-A. There are currently 30 teams classified at the Double-A level, one for each team in Major League Baseball, organized into three leagues: Double-A Central, Double-A Northeast, and Double-A South. As part of the 2021 reorganization of the minor leagues, the three current Double-A leagues replaced the Texas League, Eastern League, and Southern League, respectively.
Class AA ("Double-A") was established in 1912, as the new highest classification of Minor League Baseball. Previously, Class A had been the highest level, predating the establishment of the National Association of Professional Baseball Leagues—the formal name of Minor League Baseball—in 1901.:15 Entering the 1912 season, three leagues were designated as Class AA::236
Each of these leagues had previously been in Class A.:230 Each remained in Class AA through 1945,:396 then moved into Class AAA ("Triple-A") when it was established in 1946.:15 No other leagues were designated Class AA during 1912–1945, although a Class A1 level (between Class A and Class AA) was established in 1936.:15
The contemporary Double-A classification, as the second-highest level in Minor League Baseball, was established in 1946. Entering that season, the three aforementioned leagues in Class AA all moved to the newly established Triple-A, and Class A1 became Double-A with two leagues::401
- Southern Association, previously Class A1 (1936–1945)
- Texas League, previously Class A1 (1936–1942; idle for three seasons during World War II)
The Texas League would remain in Double-A for the next 75 years. During this time, there were limited changes to leagues at the Double-A level:
- 1955: the Mexican League, previously independent, was classified as Double-A:732
- 1961: final season of the Southern Association:743
- 1963: the Eastern League and original South Atlantic League were moved from Class A to Double-A:731, 743
- 1964: the original South Atlantic League was reconstituted as the Southern League:733
- 1967: the Mexican League moved to Triple-A:732
Entering the 2020 minor league season (which was not played, due to the COVID-19 pandemic) the Texas League had been in Double-A since 1946, the Eastern League since 1963, and the Southern League since 1964. Prior to the 2021 season, Major League Baseball (MLB) reorganized the minor leagues, resulting in the discontinuation of all three Double-A leagues, which were then succeeded by Double-A Central, Double-A Northeast, and Double-A South.
The Double-A classification usually hosts developing players that have been part of professional baseball for only a couple of years. These players can get to the Double-A level by earning a promotion from any of the lower-level leagues, with Class A-Advanced ("High-A") being immediately below Double-A in the minor league hierarchy.
The step up to the Double-A level can be one of the hardest promotions for such players because it is the level at which pitchers need to have a good off-speed pitch in their repertoires. In addition, it is the level where fastball-only hitters need to learn how to hit off-speed pitches, or their hopes of advancing to the majors will diminish. Some players may be placed in Double-A to begin their minor league careers, usually veterans from foreign leagues or top prospects out of college. Additionally, major league clubs sometimes send players to their Double-A team to rehabilitate from injuries.
While Triple-A is the highest level in the minor leagues, players may also advance to the major leagues directly from Double-A. For example, within the Toronto Blue Jays organization, 17 position players were promoted from Double-A directly to MLB during 1978–2018; approximately one player every two seasons. As players at the Double-A level are, generally, still improving their skills, it could be argued that the pure talent level is higher in Double-A than Triple-A, where there may be some stagnation of talent.
Because players are not moving back and forth from the major leagues at this level, as often happens in Triple-A, the rosters tend to be more stable. Fans of Double-A teams have a longer amount of time to get acquainted with the players, which helps create a better relationship between the team and its fans.
This section needs to be updated. The reason given is: need to update for the current Double-A leagues, once their playoff structure is known.(April 2021)
Prior to the 2021 reorganization of the minor leagues, all three active Double-A leagues played split seasons, with the Eastern League moving to that system in 2019. Teams winning their division in either half of the season qualified for the postseason, with wild card teams filling out the remaining spots in a bracket tournament, usually comprising four teams.
Prior to the 2021 reorganization of the minor leagues, each of the active Double-a leagues held its own midseason All-Star Game. From 1991 to 2002, the three combined to hold the Double-A All-Star Game between teams of American League-affiliated All-Stars and National League-affiliated All-Stars.
As a part of pace-of-play initiatives implemented in 2015, 20-second pitch clocks entered use at Double-A stadiums in 2015. In 2018, the time was shortened to 15 seconds when no runners are on base. Other significant changes implemented in 2018 included beginning extra innings with a runner on second base and limiting teams to eight mound visits during a nine-inning game. In 2019, the number of mound visits was reduced to seven, and pitchers were required to face a minimum of three consecutive batters, unless the side is retired or the pitcher is injured and unable to continue.
- The Official Professional Baseball Rules Book (PDF). New York City: Office of the Commissioner of Baseball. 2021. p. 10. Retrieved May 1, 2021 – via mlbpa.org.
- "Teams by League and Classification". Minor League Baseball. Retrieved November 8, 2020.
- Mayo, Jonathan (February 12, 2021). "MLB announces new Minors teams, leagues". MiLB.com. Minor League Baseball. Retrieved February 14, 2021.
- "National Commission Grants Minor Leaguers Everything Asked For: Big Moguls of Baseball...Establish Much Wanted Class AA". The Philadelphia Inquirer. January 5, 1912. p. 10. Retrieved April 14, 2021 – via newspapers.com.
- The Encyclopedia of Minor League Baseball. Lloyd Johnson & Miles Wolff, editors (Third ed.). Baseball America. 2007. ISBN 978-1932391176.CS1 maint: others (link)
- "What is Double AA Baseball?". SportingCharts. 2014. Retrieved March 19, 2015.
- Moore, Jeff (July 2, 2013). "Understanding Minor League Levels". The Hardball Times. Retrieved March 18, 2015.
- Hunter, Ian (May 11, 2018). "Flashback Friday: Blue Jays Position Players Who Leapt From Double-A to MLB". bluejayhunter.com. Retrieved April 14, 2021.
- Santelli, Robert; Santelli, Jenna (2010). The Baseball Fan's Bucket List: 162 Things You Must Do, See, Get, and Experience Before You Die. Running Press. p. 218. ISBN 9780762438556.
- "Dickey-Stephens Park". Arkansas Diamonds: The Ballparks of Arkansas and Their History. Archived from the original on May 5, 2015. Retrieved September 22, 2017.
- Bergeron, Angela (2008). "Feature Story - August 2008". Engineering News-Record. McGraw-Hill. Archived from the original on February 27, 2014. Retrieved September 22, 2017.
- Mock, Joe. "Hammons Field in Springfield, Missouri". Baseball Parks. Retrieved September 22, 2017.
- "ONEOK Field". Tulsa Sports Commission. 2010. Retrieved May 4, 2015.
- Reichard, Kevin (April 10, 2019). "Sod Poodles Launch Crowd-Pleasing Ballpark". Ballpark Digest. August Publications. Retrieved April 10, 2019.
- Goldberg-Strassler, Jesse (November 19, 2012). "Whataburger Field / Corpus Christi Hooks". Ballpark Digest. Retrieved May 4, 2015.
- Goldberg-Strassler, Jesse (November 14, 2012). "Dr Pepper Ballpark / Frisco RoughRiders". Ballpark Digest. Retrieved May 4, 2015.
- "Security Bank Ballpark". Stadiums USA. Archived from the original on May 8, 2016. Retrieved September 22, 2017.
- Knight, Graham (September 17, 2010). "NYSEG Stadium". Baseball Pilgrimages. Retrieved May 4, 2015.
- Mock, Joe. "Dunkin' Donuts Park". www.baseballparks.com. Grand Slam Enterprises, Inc. Retrieved September 27, 2017.
- "2012 New Hampshire Fisher Cats Media Guide" (PDF). Minor League Baseball. April 9, 2012. Retrieved May 4, 2015.
- Knight, Graham (July 6, 2010). "Hadlock Field – Portland Sea Dogs". Baseball Pilgrimages. Retrieved May 4, 2015.
- Leon, Matt (May 17, 2011). "Minor League Ballpark Guide". KYW. Philadelphia. Retrieved May 4, 2015.
- "Akron RubberDucks Canal Park". Minor League Baseball. November 27, 2012. Retrieved September 27, 2017.
- "2012 Altoona Curve Media Guide". Minor League Baseball. 2012. Retrieved May 4, 2015.
- "Bowie Baysox Baysox/Stadium Info". Minor League Baseball. March 11, 2009. Retrieved May 4, 2015.
- "Jerry Uth Park". Erie County Convention Center Authority. Archived from the original on July 30, 2012. Retrieved August 3, 2012.
- Reichard, Kevin (June 28, 2010). "Metro Bank Park / Harrisburg Senators". Ballpark Digest. Retrieved May 4, 2015.
- O'Connor, John (March 27, 2010). "Bleacher Banners Give Diamond New Look, Fewer Seats". Richmond Times-Dispatch. Retrieved February 23, 2014.
- "Regions Field Birmingham Barons". Minor League Baseball. January 27, 2012. Retrieved May 4, 2015.
- Knight, Graham (July 27, 2010). "AT&T Field". Baseball Pilgrimages. Retrieved May 4, 2015.
- Gattis, Paul (April 15, 2019). "Countdown is on: 1 year from today until first Trash Pandas game in Madison". AL.com. Retrieved September 5, 2019.
- Reichard, Kevin (May 1, 2015). "Smokies Park / Tennessee Smokies". Ballpark Digest. Retrieved May 4, 2015.
- Harris, Chris (February 12, 2015). "A Walking Tour of MGM Park". Minor League Baseball. Retrieved May 4, 2015.
- "Mississippi Braves Stadium Information". Minor League Baseball. November 13, 2008. Retrieved May 4, 2015.
- "Riverwalk Stadium Information". Minor League Baseball. February 25, 2013. Retrieved May 4, 2015.
- Pillon, Dennis (April 20, 2012). "Pensacola's Class AA Baseball Fever Still Going Strong". Press-Register. Mobile. Retrieved May 4, 2015.
- "Texas League Playoff Procedures". Retrieved March 28, 2015.
- "Eastern League Playoff Procedures". Retrieved March 28, 2015.
- "Southern League Playoff Procedures". Retrieved March 28, 2015.
- "Important Dates". Minor League Baseball. Retrieved April 24, 2020.
- "SL Sets First All-Star Tilt". The Orlando Sentinel. Orlando. July 11, 1991. p. B-4 – via Newspapers.com.
- Gonzalez, Roberto (July 11, 2002). "End Comes in Seventh". Hartford Courant. Hartford. p. C1 – via Newspapers.com.
- Acquavella, Katherine (January 5, 2021). "MLB delays start of 2021 season for most minor-league teams, per report". CBS Sports. Retrieved May 5, 2021.
- "Sea Dogs 2021 Season Schedule" (PDF). Portland Sea Dogs. Retrieved May 5, 2021 – via mlbstatic.com.
- Jackson, Josh (January 15, 2015). "Triple-A, Double-A to Implement Pitch Clock". MILB.com. Retrieved April 20, 2015.
- "MiLB announces pace-of-play rules for 2018". MILB.com. March 14, 2018. Retrieved March 15, 2018.
- "MiLB announces pace-of-play rules for 2019". MILB.com. March 29, 2019. Retrieved March 30, 2019.