In baseball, the umpire is the person charged with officiating the game, including beginning and ending the game, enforcing the rules of the game and the grounds, making judgment calls on plays, and handling the disciplinary actions. The term is often shortened to the colloquial form ump. They are also sometimes addressed as blue at lower levels due to the common color of the uniform worn by umpires. In professional baseball, the term blue is seldom used by players or managers, who instead call the umpire by name. Although games were often officiated by a sole umpire in the formative years of the sport, since the turn of the 20th century, officiating has been commonly divided among several umpires, who form the umpiring crew. The position is analogous to that of a referee in many other sports.
William Joseph Klem, born William Joseph Klimm, known as the "Old Arbitrator" and the "father of baseball umpires", was a National League (NL) umpire in Major League Baseball from 1905 to 1941. He worked 18 World Series, which is a major league record. Klem was posthumously inducted into the Baseball Hall of Fame in 1953.
James Bremond Evans is a former umpire in Major League Baseball (MLB) who worked in the American League (AL) from 1971 to 1999, and ran a professional umpiring school from 1990 through 2012.
Donald Anton Denkinger is a former Major League Baseball umpire who worked in the American League from 1969 to 1998. Denkinger wore uniform number 11, when the AL adopted uniform numbers in 1980. He is best remembered for an incorrect safe call he made at first base in Game 6 of the 1985 World Series, which came to be known as The Call.
James Gilbert McKean was a Canadian umpire in Major League Baseball (MLB) who worked in the American League (AL) from 1974 to 1999, and in both major leagues in 2000 and 2001. He umpired in the World Series in 1979, 1985 and 1995. He also officiated in five American League Championship Series and three All-Star games, calling balls and strikes for the last game, as well as the 1981, 1995 and 1999 American League Division Series. He wore uniform number 8 after the AL adopted uniform numbers in 1980.
Larry Sanders McCoy is a former umpire in Major League Baseball who worked in the American League from 1970 to 1999.
Joseph Norbert Brinkman is an American former umpire in Major League Baseball (MLB) who worked in the American League (AL) from 1972 to 1999 and throughout both major leagues from 2000 until his retirement during the 2006 season.
Stephen Michael Palermo was an umpire in Major League Baseball who worked in the American League from 1977 to 1991. His field career ended when he was shot in the back following his decision to intervene and apprehend the assailants in an altercation outside Campisi's, a Dallas Italian restaurant. He wore uniform number 14 when the American League began using uniform numbers for its umpires in 1980, and the number was never reassigned to another AL umpire until after the AL and NL umpire staffs were unified by MLB in 2000.
Michael Eugene Reilly is a former Major League Baseball umpire who worked in the American League from 1977 to 1999 and throughout both major leagues from 2000 to 2010. Upon Ed Montague's retirement in February 2010, Reilly became Major League Baseball's senior umpire; his 4,362 career games ranked ninth in major league history entering the 2010 season. He retired on February 23, 2011, along with fellow umpires Jerry Crawford and Chuck Meriwether.
Edwin Durwood Merrill was an American umpire in Major League Baseball (MLB) who worked in the American League for 23 seasons (1977–1999).
Gerald Joseph Crawford is a former umpire in Major League Baseball. He first umpired in the National League from 1977 to 1999, then worked in both major leagues from 2000 to 2010.
Edward George Barrett is an American retired Major League Baseball umpire. He joined the American League's staff in 1994, and has worked throughout both major leagues since 2000. Promoted to crew chief in 2013, Barrett worked in 33 play-off series, including five World Series. He retired following the 2022 season.
Timothy Joseph Tschida is a former umpire in Major League Baseball. He joined the American League's full-time staff in 1986, and worked in both major leagues from 2000 until his retirement following the 2012 season.
James Alfred Joyce III is an American former professional baseball umpire who worked in the American League (AL) from 1987 to 1999 and throughout Major League Baseball (MLB) from 2000 to 2016. He wore uniform number 6 while in the AL and number 66 for MLB. His loud and enthusiastic strike call drew comparisons to that of retired umpire Bruce Froemming. Though his umpiring was generally praised by players and coaches, Joyce is best known for his incorrect call in Armando Galarraga's near-perfect game in June 2010.
Louis John DiMuro was an American umpire in Major League Baseball who worked in the American League from 1963 until his death.
Martin John Springstead was an umpire in Major League Baseball who worked in the American League from 1966 to 1985 and had since worked as an umpire supervisor. He was the youngest umpire ever to serve as crew chief in the World Series, heading the staff for the 1973 Series at the age of 36 years and 3 months.
Jerome August Neudecker was an American Major League Baseball umpire who worked in the American League from 1966 to 1985. He wore number 6 when the league adopted uniform numbers in 1980.
James Norris Reynolds IV is a former American Major League Baseball umpire. He joined the major league staff in 1999 and was promoted to crew chief for the 2020 season. Reynolds wore uniform number 77. He retired following the 2022 season.
William Edward John Deegan is a former Major League Baseball umpire who worked in the American League from 1971 to 1980. Deegan wore uniform number 17 when the American League adopted them for its umpires in 1980, later worn by John Hirschbeck.
Alan Marshall Clark is a former professional baseball umpire who worked in the American League from 1976 to 1999, and throughout both Major Leagues in 2000 and 2001. He was fired for misuse of a credit card issued for professional expenses. Three years later, pled guilty to mail fraud for his involvement in a collectibles-selling scheme.
