Overview
The American League West is one of Major League Baseball's six divisions. The division has five teams as of the 2013 season, but had four teams from 1994 to 2012, and had as many as seven teams before the 1994 realignment. Although its teams currently only reside along the west coast and in Texas, historically the division has had teams as far east as Chicago and Minnesota. From 1998 (when the NL West expanded to five teams) to 2012, the AL West was the only MLB division with four teams.
History
When MLB split into divisions for the season, the American League, unlike the National League, split its 12 teams strictly on geography. The six teams located in the Eastern Time Zone were all placed in the AL East, and the remaining six were placed in the new AL West.
When the second incarnation of the Washington Senators announced their intention to move to the Dallas-Fort Worth area for the 1972 season and become the Texas Rangers, American League owners voted to switch the Rangers with the Milwaukee Brewers, who began as the Seattle Pilots in 1969. The Chicago White Sox asked the AL to move from West to East, citing that five of the original eight American League franchises were in the East. The Oakland Athletics and Minnesota Twins objected to the White Sox' request; the Twins also did not want the Brewers to leave the West.
In 2013, the Houston Astros went from the National League Central to the AL West. That move gives all six MLB divisions an equal five teams and both leagues an equal 15 teams each.
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