A tie-breaker was required in Major League Baseball (MLB) when two or more teams were tied at the end of the regular season for a postseason position such as a league pennant (prior to the introduction of the League Championship Series in 1969), a division title, or a wild card spot. Until 2022, both the American League (AL) and the National League (NL) used a one-game playoff format for tie-breakers, although the NL used a best-of-three series prior to 1969, when the leagues were split into divisions. As these tie-breaker games counted as part of the regular season and MLB teams (American League beginning in 1961, and National League beginning in 1962) have 162-game regular season schedules, the tie-breaker games were sometimes referred to as "Game 163".[1][2] In 2022, as part of the new Collective Bargaining Agreement to end the 2021–22 Major League Baseball lockout, tiebreaker games were replaced with statistical tiebreaker procedures.[3][4][5]
Sixteen tie-breakers – 12 single-game and four series – have been played in MLB history. In baseball statistics, tie-breaker games counted as regular season games with all events in them counted towards regular season statistics. This had implications on statistical races, such as when Matt Holliday won the batting average and runs batted in titles thanks in part to his performance in the 2007 tie-breaker.[6] Home-field advantage for tie-breakers was determined by a coin flip through the 2008 season, after which performance-based criteria, starting with head-to-head record of the tied teams, were put in place.[7]
Although there have been no situations requiring a tie-breaker between more than two teams, it was possible. In 2007, for example, the Philadelphia Phillies, New York Mets, San Diego Padres, Colorado Rockies, and Arizona Diamondbacks finished the season within two games of one another.[8] The possibility existed for as many as four teams to be locked in a series of tie-breakers that year to decide the NL East, West, and Wild Card.[9] Similarly, late in the 2012 season the possibility existed for the New York Yankees, Baltimore Orioles, and either the Texas Rangers or Oakland Athletics to all finish with the same record. This could have required the teams to play a complex set of multiple games to determine divisional and wild card winners, a situation which Jayson Stark described as potentially "baseball's worst scheduling nightmare."[10]
Game163
was invoked but never defined (see the help page).