The American League Division Series (ALDS) in Major League Baseball selects which two American League clubs will proceed to the American League Championship Series. The Division Series comprises two best-of-five series involving the three division champions and the wild-card playoff winner.
The American League Championship Series (ALCS) is a best-of-seven playoff and one of two League Championship Series that makeup Major League Baseball’s last stage. The champions of the two American League Division Series compete in it. The winner of the ALCS takes home the AL pennant and goes to the World Series, MLB’s championship series, where they will face the winner of the National League Championship Series. The American League Championship Series (ALCS) began in 1969 as a best-of-five playoff and continued in that format until 1985 when it switched to its current best-of-seven format.
Brief History of the ALDS
The Division Series was created in 1981 as a one-time event in response to a midseason strike, with the teams in the first place before the strike competing against the teams in first place after the strike. When Major League Baseball (MLB) reorganized each league into three divisions, albeit in a different arrangement than in 1981, it was reinstated permanently in 1994.
The system required is a split-season system for the maiden edition of (DPS) divisional playoff series in 1981, the title was clinched by the New York Yankees during the Eastern Division in a five game match up against the Milwaukee Brewers, while Kansas City Royals was defeated by the Oakland Athletics in the Western Division. With twenty appearances in the division series, including the 2018 postseason, the Yankees have the most. The Toronto Blue Jays and Houston Astros were the last American League clubs to play in the ALDS for the first time in 2015. The Astros had been in the National League until 2012 and had been in seven National League Division Series.
Determining the matchups in ALDS
The ALDS is a best-of-five series in which the wild card team plays the divisional winner with the best winning percentage in the regular season in one series, and the other two division winners meet in the other series, with the team with the second-best winning percentage receiving home-field advantage. The winners of the two series advance to the best-of-seven ALCS. Thus according to Nate Silver, the introduction of these postseason series, particularly the wild card, has pushed clubs to prioritize “going to the playoffs” above “winning the pennant” as the primary aim of the regular season.
Beginning with the 2012 season, the wild card club that advances to the Division Series faced the number one seed, regardless of whether they were in the same division. The winners of the two series advance to the best-of-seven ALCS. Except for the wild card club, which never obtains home-field advantage, the team with the higher regular-season record earns home-field advantage.
Brief History of the ALCS
Before 1969, the winner of the American League was chosen by the team with the most incredible win-loss record at the end of the regular season. There was just one ad hoc single-game playoff staged under this method, in 1948, due to a draw. The ALCS began in 1969, when the American League was split into two divisions, East and West. The division winners faced off in a best-of-five series to determine who would proceed to the World Series. The format was modified to best-of-seven in 1985. Due to a broken season caused by a players’ strike, a division series was contested in 1981.
The league was reorganized into three divisions in 1994, with the division champions and a wild-card club proceeding to the American League Division Series, a best-of-five knockout series. The round’s winners progressed to the best-of-seven ALCS. The playoffs were extended further in 2012, with two wild card teams facing off in a one-game wild-card round to determine which club goes to the division series. The playoffs then continued as previously once the wild card round ended. This is the current system in use.
Since the expansion to best-of-seven, the ALCS and NLCS have always been played in a 2–3–2 format: Games 1, 2, 6, and 7 are played in the stadium of the team with home-field advantage, and Games 3, 4, and 5 are played in the stadium of the team without. When one side wins four games in a row, the series is over. Since 1998, home-field advantage has been awarded to the club with the higher regular-season record, except the team that qualified for the postseason as the Wild Card, which does not get home-field advantage.
If both teams have similar regular-season records, the club with the better head-to-head record gets home-field advantage. Home-field advantage rotated between the two divisions from 1969 to 1993, and from 1995 to 1997, home-field advantage was established before the season.
The Milwaukee Brewers, who played in the American League from 1969 to 1997, and the Houston Astros, who played in the National League from 1962 to 2012, are the only teams in the ALCS and the NLCS. The Astros are the only club to have won both the NL and AL Championship Series. Every current American League team has competed in the American League Championship Series.
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