  the league championship series (lcs) is the official name for the semifinal round of postseason play in major league baseball which has been conducted since 1969. in 1981, and since 1995, the two annual series have matched up the winners of the division series, and the winners advance to meet in the world series. the league championship series was promulgated in 1969, when both the national league and the american league increased in size from ten teams to twelve with the addition, via expansion, of the montreal expos and san diego padres to the former and the kansas city royals and seattle pilots (now the milwaukee brewers of the nl) to the latter. concomitant with this, both leagues formed eastern and western divisions, the first-place teams from which faced off in the lcs. originally, the league championship series were best-of-five using the 2â3 format in which the team without home field advantage hosted the first two games and the team with it hosted the remaining game(s), making it impossible for the disadvantage team to win the series at home. it also allowed those teams the unusual luxury of starting a series at home, possibly having home field advantage in a three game series, and a guarantee that they play the maximum number of games possible at home (2). in 1985.owners propose best-of-7 league playoffs pittsburgh post-gazettebaseball adopts 7-game playoffs on trial basis palm beach post the lcs was lengthened to best-of-seven games in the 2-3-2 format with the team holding home-field advantage opening the series at home and playing the next three games on the road, before returning home for two more possible games. the disadvantage team would have had more games played at home than on the road if the series ends in five games. since 1995 the lcs has matched up the winners of the division series, which were added when both leagues realigned into three divisions, the winners thereof plus one wild card team in each league participating in the latter series, which is a best-of-five (this change was actually supposed to take place in 1994, but posts
American_League_Championship_Series Major_League_Baseball_playoffs_and_champions National_League_Championship_Series Recurring_sporting_events_established_in_1969